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=========================================================== DDDDD DDDDD SSSS D Dunfield D D S D D D Development SSSS D D D D Systems DDDDD DDDDD SSSS =========================================================== MM MM IIIIIII CCCC RRRRRR OOO CCCC M M M M I C C R R O O C C M M M I C R R O O C M M I C RRRRRR O O ----- C M M I C R R O O C M M I C C R R O O C C M M IIIIIII CCCC R R OOO CCCC =========================================================== A compact 'C' compiler for C-FLEA processors. Technical Manual Release 3.02 Revised 09-Feb-94 Copyright 1988-1994 Dave Dunfield All rights reserved MICRO-C C-FLEA Compiler Page: 1 1. INTRODUCTION This C-FLEA developers kit includes pre-configured implementations of the MICRO-C compiler, ASMCF cross assembler, and related utilities. The package provides everything you need to perform software development in either 'C' or assembler for the C-FLEA virtual processor. 1.1 Memory configuration The code produced by this compiler runs on the C-FLEA virtual processor, which can be emulated by several different host microprocessors. The exact memory layout may vary depending on the host. In the default system, the program is placed in memory at address $1000, and the stack grows down from $0FFF, while data is allocated beginning at $0000. You may run the code in other configurations, by re-configuring the memory setup in the PREFIX.ASM and MIDDLE.ASM files located in the LIBCF sub directory. Virtually any memory configuration within the limits of a single 64K address space can be handled by our PC based EMCF Virtual Machine Simulator. 1.2 Code Portability With few exceptions, this compiler follows the syntax of the "standard" UNIX compiler (within its subset of the language). Programs written in MICRO-C should compile with few changes under other "standard" compilers. 1.2.1 Unsupported Features: MICRO-C does not currently support the following features of standard 'C': Long / Double / Float / Enumerated data types, Typedef and Bit fields. 1.2.2 Additional Features MICRO-C provides a few additional features which are not always included in "standard" 'C' compilers: Unsigned character variables, Nested comments, 16 bit character constants, Inline assembly code capability. MICRO-C C-FLEA Compiler Page: 2 1.3 The compiling process There are five programs which work together to completely compile a MICRO-C program: The PREPROCESSOR (MCP) takes the original 'C' source file, performs MACRO expansion and incorporates the contents of INCLUDE files to get a "pure" 'C' output file. A less powerful pre-processor is also contained inside the COMPILER, which allows this step to be skipped for programs which use only simple pre-processor functions. The COMPILER (MCCCF) reads a file containing a 'C' source program, and translates it into an equivalent assembly language program. The OPTIMIZER (MCOCF) reads the assembly language output from the compiler identifying and replacing "general" code produced by the compiler with more efficent code which is equivalent in specific cases. This step is optional, allowing you to choose between faster compile time and greater program efficency. The SOURCE LINKER (SLINK) combines the assembly language output from the compiler with any required routines from the runtime library, to create an entire program file. The ASSEMBLER (ASMCF) assembles this program file into a downloadable binary image in either INTEL or MOTOROLA hex file format. MICRO-C C-FLEA Compiler Page: 3 2. THE COMMAND CO-ORDINATOR 'CC' is a utility which co-ordinates the execution of programs required for each step of the compilation process to provide a simple "one step" compilation command. This MICRO-C package includes a version of the command co-ordinator which handles the commands necessary to compile for the C-FLEA processor (MCP, MCCCF, MCOCF, SLINK, ASMCF). 2.1 The CCF command The format of the 'CCF' command is: CCF <name> [options] 2.1.1 Command line options -A - produce ASSEMBLER (.ASM) output file -C - Include 'C' source as comments in ASM files -F - Fold identical string constants. -I - Output INTEL hex file (default is MOTOROLA) -K - KEEP all temporary files (do not delete) -L - Generate assembly .LST file -M - Invoke xasm MACRO processor (See XASM manual) -O - OPTIMIZE the output code (using MCOCF) -P - use the extended PRE-PROCESSOR (MCP) -Q - QUIET mode (suppress informational messages) -X - produce eXtended ASM file (includes libraries) H=mcdir - specify MICRO-C home directory T=mctmp - specify prefix for TEMPORARY files name=xx - Predefine macro symbol (use with -P only) When executing the sub-commands, CCF will search the MICRO-C home directory, as well as any directories specified in the 'PATH' environment variable. Libraries are accessed from the MICRO-C home directory only. The environment variable 'MCDIR' is examined to determine the path to the MICRO-C home directory. If MCDIR is not defined, CCF will assume the string '\MC'. You may override this directory by using the 'h=' option on the command line. Intermediate results from each command are stored in "temporary" files, which are fed as input to the next command. Temporary files will be deleted once they are no longer needed, except in the case where a command fails. When this happens, any temporary file which was being used as input to that command will not be deleted, allowing you to examine it for the cause of the error. MICRO-C C-FLEA Compiler Page: 4 The environment variable 'MCTMP' is examined to determine a prefix to prepend to temporary file names. If MCTMP is not defined, CCF assumes the default prefix of '$'. You may override this prefix by using the 't=' option on the command line. Here are example 'SET' commands suitable for inclusion in the AUTOEXEC.BAT file, of an IBM/PC based MICRO-C system which has the home directory in 'C:\MC', and a TEMP directory on a RAMDISK as drive 'D': SET MCDIR=C:\MC SET MCTMP=D:\TEMP\ (Note trailing '\') The '-A' option causes CCF to bypass the assembler and linker, and produce an assembly source file (<name>.ASM) as the output file. If the '-C' option is also used, this file will contain the 'C' source code in the form of comments. NOTE: The source code inserted by '-C' will restrict the optimizer to operate only on sections of code produced by a single 'C' line. The '-F' option causes the compiler to "fold" its literal pool (the area of memory where string constants are stored). This means that identical strings not contained in explicit variables, will occur only once in memory. Since most programs never modify such strings, it is usually safe to do this. Note however that this is a violation of the 'C' standard ("The 'C' Programming Language" page 181 - "All strings, even when written identically, are distinct"), and it is possible to write programs which will not work properly when this option is used. The '-X' option is similar to '-A', except that the program is passed through the source linker, resulting in a ".ASM" file containing the complete program, including startup code and library functions. The '-M' option causes CCF to invoke the xasm MACRO processor, allowing macros to be used in your inline assembly code (See XASM manual). For the sake of efficency, this is done BEFORE the program is passed through the source linker. This means that macros in files from the library will NOT be processed. If library files contain macros, they should be processed BEFORE they are placed in the library. If any of the programs executed by CCF fail to complete properly, CCF will show the message "PGM failed (RC)", where PGM is the name of the offending program, and RC is the DOS return code value. Common RC values under MSDOS are: 2 - Command not found (Check MCDIR and PATH setup) 3 - Path not found (Check MCDIR and PATH setup) 254 - Program found errors during processing 255 - Program was invoked with incorrect arguments MICRO-C C-FLEA Compiler Page: 5 3. THE MICRO-C PROGRAMMING LANGUAGE The following pages contain a brief summary of the features and constructs implemented in MICRO-C. This document does not attempt to teach 'C' programming, and assumes that the reader is familiar with the language. 3.1 Constants The following forms of constants are supported by the compiler: <num> - Decimal number (0 - 65535) 0<num> - Octal number (0 - 0177777) 0x<num> - Hexidecimal number (0x0 - 0xffff) '<char>' - Character (1 or 2 chars) "<string>" - Address of literal string. The following "special" characters may be used within character constants or strings: \n - Newline (line-feed) (0x0a) \r - Carriage Return (0x0d) \t - Tab (0x09) \f - Formfeed (0x0c) \b - Backspace (0x08) \<num> - Octal value <num> (Max. three digits) \x<num> - Hex value <num> (Max. two digits) \<char> - Protect character <char> from input scanner. 3.2 Symbols Symbol names may include the characters 'a'-'z', 'A'-'Z', '0'-'9', and '_'. The characters '0'-'9' may not be used as the first character in the symbol name. Symbol names may be any length, however, only the first 15 characters are significant. The "char" modifier may be used to declare a symbol as an 8 bit wide value, otherwise it is assumed to be 16 bits. eg: char input_char; The "int" modifier may be used to declare a symbol as a 16 bit wide value. This is assumed if neither "int" or "char" is given. eg: int abc; The "unsigned" modifier may be used to declare a symbol as an unsigned positive only value. Note that unlike some 'C' compilers, this modifier may be applied to a character (8 bit) variable. eg: unsigned char count; MICRO-C C-FLEA Compiler Page: 6 The "extern" modifier causes the compiler to be aware of the existance and type of a global symbol, but not generate a definition for that symbol. This allows the module being compiled to reference a symbol which is defined in another module. This modifier may not be used with local symbols. eg: extern char getc(); A symbol declared as external may be re-declared as a non-external at a later point in the code, in which case a definition for it will be generated. This allows "extern" to be used to inform the compiler of a function or variable type so that it can be referenced properly before that symbol is actually defined. The "static" modifier causes global symbols to be available only in the file where they are defined. Variables or functions declared as "static" will not be accessable as "extern" declarations in other object files, nor will they cause conflicts with duplicate names in those files. eg: static int variable_name; When applied to local symbols, the "static" modifier causes those variables to be allocated in a reserved area of memory, instead of on the processor stack. This has the effect that the contents of the variable will be retained between calls to the function. It also means that the variable may be initialzed at compile time. The "register" modifier indicates to the code generator that this is a high priority variable, and should be kept where it is easy to get at. Since its interpretation depends on the code generator, it is often ignored in simple implementations. See "Functions" for a special use of "register" when defining a function. eg: register unsigned count; Symbols declared with a preceeding '*' are assumed to be 16 bit pointers to the declared type. eg: int *pointer_name; Symbol names declared followed by square brackets are assumed to be arrays with a number of dimensions equal to the number of '[]' pairs that follow. The size of each dimension is identified by a constant value contained within the corresponding square brackets. eg: char array_name[5][10]; MICRO-C C-FLEA Compiler Page: 7 3.2.1 Global Symbols Symbols declared outside of a function definition are considered to be global and will have memory permanently reserved for them. Global symbols are defined by name in the output file, allowing other modules to access them. Note that the compiler IS case sensitive, however if the assembler you are using is NOT, you must be careful not to declare any global symbols with names that differ only in case. All non-initialized global variables are generated at the very end of the output file, after the literal pool is dumped. Since non-initialized globals do not generate object code, this allows them to be excluded from the image file when it is saved to disk. Global variables may be initialized with one or more values, which are expressed as a single array of integers REGUARDLESS of the size and shape of the variable. If more than one value is expressed, '{' and '}' must be used. eg: int i = 10, j[2][2] = { 1, 2, 3, 4 }; When arrays are declared, a null dimension may be used as the dimension size, in which case the size of the array will default to the number of initialized values. eg: int array[] = { 1, 2, 3 }; Initialized global variables are automatically saved within the code image, insuring that the initial values will be available at run time. Any non-initialized elements of an array which has been partly initialized will be set to zero. Non-initialized global variables are not preset in any way, and will be undefined at the beginning of program execution. 3.2.2 Local Symbols Symbols declared within a function definition are allocated on the stack, and exist only during the execution of the function. To simplify the allocation and de-allocation of stack space, all local symbols must be declared at the beginning of the function before any code producing statements are encountered. MICRO-C does not support initialization of non-static local variables in the declaration statement. Since local variables have to be initialized every time the function is entered, you can get the same effect using assignment statements at the beginning of the function. No type is assumed for arguments to functions. Arguments must be explicitly declared, otherwise they will be undefined within the scope of the function definition. MICRO-C C-FLEA Compiler Page: 8 3.2.3 More Symbol Examples /* Global variables are defined outside of any function */ char a; /* 8 bit signed */ unsigned char b; /* 8 bit unsigned */ int c; /* 16 bit signed */ unsigned int d; /* 16 bit unsigned */ unsigned e; /* also 16 bit unsigned */ extern char f(); /* external function returning char */ static int g; /* 16 bit signed, local to file */ int h[2] = { 1, 2 }; /* initialized array (2 ints) */ main(a, b) /* "int" function containing code */ /* Function arguments are defined between function name and body */ int a; /* 16 bit signed */ unsigned char *b; /* pointer to 8 bit unsigned */ { /* Local variables are defined inside the function body */ /* Note that in MICRO-C, only "static" locals can be initialized */ unsigned c; /* 16 bit unsigned */ static char d[5]; /* 8 bit signed, reserved in memory */ static int e = 1; /* 16 bit signed, initial value is 1 */ /* Function code goes here ... */ c = 0; /* Initialize 'c' to zero */ strcpy(d, "Name"); /* Initialize 'd' to "name" */ } MICRO-C C-FLEA Compiler Page: 9 3.3 Arrays & Pointers When MICRO-C passes an array to a function, it actually passes a POINTER to the array. References to arrays which are arguments are automatically performed through the pointer. This allows the use of pointers and arrays to be interchangable through the context of a function call. Ie: An array passed to a function may be declared and used as a pointer, and a pointer passed to a function may be declared and used as an array. 3.4 Functions Functions are essentially initialized global symbols which contain executable code. MICRO-C accepts any valid value as a function reference, allowing some rather unique (although non-standard) function calls. For example: function(); /* call function */ variable(); /* call contents of a variable */ (*var)(); /* call indirect through variable */ (*var[x])(); /* call indirect through indexed array */ 0x5000(); /* call address 0x5000 */ Since this is a single pass compiler, operands to functions are evaluated and pushed on the stack in the order in which they are encountered, leaving the last operand closest to the top of the stack. This is the opposite order from which many 'C' compilers push operands. For functions with a fixed number of arguments, the order of which operands are passed is of no importance, because the compiler looks after generating the proper stack addresses to reference variables. HOWEVER, functions which use a variable number of arguments are affected for two reasons: 1) The location of the LAST arguments are known (as fixed offsets from the stack pointer) instead of the FIRST. 2) The symbols defined as arguments in the function definition represent the LAST arguments instead of the FIRST. If a function is declared as "register", it serves a special purpose and causes the accumulator to be loaded with the number of arguments passed whenever the function is called. This allows the function to know how many arguments were passed and therefore determine the location of the first argument. MICRO-C C-FLEA Compiler Page: 10 3.5 Structures & Unions Combinations of other variable types can be organized into STRUCTURES or UNIONS, which allow them to be manipulated as a single entity. In a structure, the individual items occur sequentially in memory, and the total size of the structure is the sum of its elements. Structures are usually used to create "records", in which related items are grouped together. An array of structures is the common method of implementing an "in-memory" database. A union is similar to a structure, except that the individual items are overlaid in memory, and the total size of the union is the size of its largest element. Unions are usually used to allow a single block of memory to be accessed as different 'C' variable types. An example of this would be in handling a message received in memory, in which a "type" byte indicates how the remainder of the message data should be interpreted. Here are some example of how structures are defined and used (unions are defined and used in an identical manner, except that the word 'union' is substituted for 'struct'): /* Create structure named 'data' with 'a,b,c & d' as members */ struct { int a; int b; char c; char d; } data; /* Create structure template named 'mystruc'... */ /* No actual structure variable is defined */ struct mystruc { int a; int b; char c; char d; }; /* Create structure named 'data' using above template */ struct mystruc data; /* Create structure template 'mystruc', AND define a */ /* structure variable named 'data' */ struct mystruc { int a; int b; char c; char d; } data; MICRO-C C-FLEA Compiler Page: 11 /* Create an array of structures, a pointer to a structure */ /* and an array of pointers to a structure * struct mystruct array[10], *pointer, *parray[10]; /* To set value in structure variable/members */ data.a = 10; /* Direct access */ array[1].b = 10; /* Direct array access */ pointer->c = 'a'; /* Pointer access */ parray[2]->d = 'b'; /* Pointer array access */ /* To read value in structure variable/members */ value = data.a; /* Direct access */ value = data[1].b; /* Direct array access */ value = pointer->c; /* Pointer access */ value = parray[2]->d; /* Pointer array access */ 3.5.1 Notes on MICRO-C structure implementation: Structures and Unions as implemented in MICRO-C are similar to the implementation of the original UNIX 'C' compiler, and are bound by similar limitations, as well as a few MICRO-C specific ones. Here is a list of major differences when compared to a modern ANSI compiler: All structure and member names MUST be unique within the scope of the definition. A special case exists, where common member names may be used in multiple structure templates if they have EXACTLY the same type and offset into the structure. This also saves symbol table memory, since only one copy of the member definition is actually kept. MICRO-C does NOT pass entire structures to functions on the stack. Like arrays, MICRO-C passes structures by ADDRESS. Structure variables which are function arguments are accessed through pointers. For source code compatibility with compilers which do pass the entire structure, if you declare the argument as a direct (non-pointer) structure, the direct ('.') operator is used to dereference it, even though it is actually a pointer reference. If you MUST have a local copy of the structure, use something like: func(sptr) struct mystruc *sptr; { struct mystruc data; memcpy(data, sptr, sizeof(data)); ... } MICRO-C C-FLEA Compiler Page: 12 To obtain the size of a structure from its template name, use the 'struct' keyword in conjunction with the 'sizeof' operator. In the above example, you could replace 'sizeof(data)' with 'sizeof(struct mystruc)'. To obtain the size of a structure member, you must specify it in the context of a structure reference with another symbol: sizeof(variable.member) or sizeof(variable->member) NOTE: The current compiler allows almost any symbol to the left of the '.' or '->' operator in a 'sizeof', however future versions of the compiler may insist on a structure variable or a pointer to structure variable. Pointers to structures are internally stored as pointers to 'char', and therefore will only increment/decrement by 1 when ++/-- is used. To advance a pointer by the size of a structure, use: ptr += sizeof(struct mystruc) The 'struct' and 'union' keywords are not accepted in a TYPECAST. This is most commonly used to setup a pointer to a structure. Since MICRO-C stores its pointers to structures as pointers to char, you can use (char*) as the typecast, and get the same functionality. A structure name by itself (without '.member') acts in a manner similar to a character array name. With no operation, the address of the structure is returned. You can also use '[]' to access individual bytes in the structure by indexing, although doing so is highly non-portable. MICRO-C allows static or global structures to be initialized in the declaration, however the initial values are read as an array of bytes, and are assigned directly to structure memory without regard for the type or size of its members: struct mystruc data = { 0, 1, 0, 2, 3, 4 }; /* A=0:1, B=0:2, C=3, D=4 */ You can use INT and CHAR to switch back and forth between word/byte initialization within the value list: struct mystruct data = { int 0, 1, char 2, 3 }; /* A=0, B=1, C=2, D=3 */ MICRO-C does not WORD ALIGN structure elements. When using a processor which requires word alignment, it is the programmers responsibility to maintain alignment, using filler bytes etc. when necessary. MICRO-C C-FLEA Compiler Page: 13 3.6 Control Statements The following control statements are implemented in MICRO-C: if(expression) statement; if(expression) statement; else statement; while(expression) statement; do statement; while expression; for(expression; expression; expression) statement; return; return expression; break; continue; switch(expression) { case constant_expression : statement; ... break; case constant_expression : statement; ... break; . . . default: statement; } label: statement; goto label; asm "..."; asm { ... } MICRO-C C-FLEA Compiler Page: 14 3.6.1 Notes on Control Structures 1) Any "statement" may be a single statement or a compound statement enclosed within '{' and '}'. 2) All three "expression"s in the "for" command are optional. 3) If a "case" selection does not end with "break;", it will "fall through" and execute the following case as well. 4) Expressions following 'return' and 'do/while' do not have to be contained in brackets (although this is permitted). 5) Label names may preceed any statement, and must be any valid symbol name, followed IMMEDIATELY by ':' (No spaces are allowed). Labels are considered LOCAL to a function definition and will only be accessable within the scope of that function. 6) The 'asm' statement used to implement the inline assembly language capability of MICRO-C accepts two forms: asm "..."; <- Assemble single line. asm { <- Assemble multiple lines. ... } MICRO-C C-FLEA Compiler Page: 15 3.7 Expression Operators The following expression operators are implemented in MICRO-C: 3.7.1 Unary Operators - - Negate ~ - Bitwise Complement ! - Logical complement ++ - Pre or Post increment -- - Pre or post decrement * - Indirection & - Address of sizeof - Size of a object or type (type) - Typecast 3.7.2 Binary Operators + - Addition - - Subtraction * - Multiplication / - Division % - Modulus & - Bitwise AND | - Bitwise OR ^ - Bitwise EXCLUSIVE OR << - Shift left >> - Shift right == - Test for equality != - Test for inequality > - Test for greater than < - Test for less than >= - Test for greater than or equal to <= - Test for less than or equal to && - Logical AND || - Logical OR = - Assignment += - Add to self assignment -= - Subtract from self assignment *= - Multiply by self assignment /= - Divide by and reassign assignment %= - Modular self assignment &= - AND with self assignment |= - OR with self assignment ^= - EXCLUSIVE OR with self assignment <<= - Shift left self assignment >>= - Shift right self assignment MICRO-C C-FLEA Compiler Page: 16 NOTES: 1) The expression "a && b" returns 0 if "a" is zero, otherwise the value of "b" is returned. The "b" operand is NOT evaluated if "a" is zero. 2) The expression "a || b" returns the value of "a" if it is not 0, otherwise the value of "b" is returned. The "b" operand is NOT evaluated if "a" is non-zero. 3.7.3 Other Operators ; - Ends a statement. , - Allows several expressions in one statement. + Separates symbol names in multiple declarations. + Separates constants in multi-value initialization. + Separates operands in function calls. ? - Conditional expression (ternary operator). : - Delimits labels, ends CASE and separates conditionals. . - Access a structure member directly. -> - Access a structure member through a pointer. { } - Defines a BLOCK of statements. ( ) - Forces priority in expression, indicates function calls. [ ] - Indexes arrays. If fewer index values are given than the number of dimensions which are defined for the array, the value returned will be a pointer to the appropriate address. Eg: char a[5][2]; a[3] returns address of forth row of two characters. (remember index's start from zero) a[3][0] returns the character at index [3][0]; MICRO-C C-FLEA Compiler Page: 17 3.8 Inline Assembly Language Although 'C' is a powerful and flexible language, there are sometimes instances where a particular operation must be peformed at the assembly language level. This most often involves either some processor feature for which there is no corresponding 'C' operation, or a section of very time critical code. MICRO-C provides access to assembly language with the 'asm' statement, which has two basic forms. The first is: asm "..." ; In this form, the entire text contained between the double quote characters (") is output as a single line to the assembler. Note that a semicolon is required, just like any other 'C' statement. Since this is a standard 'C' string, you can use any of the "special" characters, and thus you could output multiple lines by using '\n' within the string. Another important characteristic of it being a string is that it will be protected from pre-processor substitution. The second form of the 'asm' statement is: asm { ... } In this form, all lines between '{' and '}' are output to the assembler. Any text following the opening '{' (on the same line) is ignored. Due to the unknown characteristics of the inline assembly code, the closing '}' will only be recognized when it is the first non-whitespace character on a line. The integral pre-processor will not perform substitution on the inline assembly code, however the external pre-processor (MCP) will substitute in this form. This allows you to create assembly language "macros" using MCP, and have parameters substituted into them when they are expanded: /* * This macro issues a 'SETB' instruction for its parameter */ #define setbit(bit) asm {\ SETB bit\ } /* * This macro WILL NOT WORK, since the 'bit' operand to the SETB * instruction is contained within a string and is therefore * protected from substitution by the pre-processor */ #define setbit(bit) asm " SETB bit"; MICRO-C C-FLEA Compiler Page: 18 3.9 Preprocessor Commands The MICRO-C compiler supports the following pre-processor commands. These commands are recognized only if they occur at the beginning of the input line. NOTE: This describes the limited pre-processor which is integral to the compiler, see also the section on the more powerful external processor (MCP). 3.9.1 #define <name> <replacement_text> The "#define" command allows a global name to be defined, which will be replaced with the indicated text whenever it is encountered in the input file. This occurs prior to processing by the compiler. 3.9.2 #file <filename> Sets the filename of the currently procssing file to the given string. This command is used by the external pre-processor (MCP) to insure that error messages indicate the original source file. 3.9.3 #include <filename> This command causes the indicated file to be opened and read in as the source text. When the end of the new file is encountered, processing will continue with the line following "#include" in the original file. 3.9.4 #ifdef <name> Processes the following lines (up to #else or #endif) only if the given name is defined. 3.9.5 #ifndef <name> Processes the following lines (up to #else or #endif) only if the given name is NOT defined. 3.9.6 #else Processes the following lines (up to #endif) only if the preceeding #ifdef or #ifndef was false. 3.9.7 #endif Terminates #ifdef and #ifndef NOTE: The integral pre-processor does not support nesting of the #ifdef and #idndef constructs. If you wish to nest these conditionals, you must use the external pre-processor (MCP). MICRO-C C-FLEA Compiler Page: 19 3.10 Error Messages When MICRO-C detects an error, it outputs an informational message indicating the type of problem encountered. The error message is preceeded by the filename and line number where the error occured: program.c(5): Syntax error In the above example, the error occured in the file "program.c" at line 5. The following error messages are produced by the compiler: 3.10.1 Compilation aborted The preceeding error was so severe than the compiler cannot proceed. 3.10.2 Constant expression required The compiler requires a constant expression which can be evaluated at compile time (ie: no variables). 3.10.3 Declaration must preceed code. All local variables must be defined at the beginning of the function, before any code producing statements are processed. 3.10.4 Dimension table exhausted The compiler has encountered more active array dimensions than it can handle. 3.10.5 Duplicate local: 'name' You have declared the named local symbol more than once within the same function definition. 3.10.6 Duplicate global: 'name' You have declared the named global symbol more than once. 3.10.7 Expected '<token>' The compiler was expecting the given token, but found something else. 3.10.8 Expression stack overflow The compiler has found a more complicated expression than it can handle. Check that it is of correct syntax, and if so, break it up into two simpler expressions. MICRO-C C-FLEA Compiler Page: 20 3.10.9 Expression stack underflow The compiler has made an error in parsing the expression. Check that it is of correct syntax. 3.10.10 Illegal indirection You have attempted to perform an indirect operation ('*' or '[]') on an entity which is not a pointer or array. This error will also result if you attempt to index an array with more indices than it has dimensions. 3.10.11 Illegal initialization Local variables may not be initialized in the declaration statement. Use assignments at the beginning of the function code to perform the initialization. 3.10.12 Illegal nested function You may not declare a function within the definition of another function. 3.10.13 Improper type of symbol: 'name' The named symbol is not of the correct type for the operation that you are attempting. Eg: 'goto' where the symbol is not a label. 3.10.14 Improper #else/#endif A #else or #endif statement is out of place. 3.10.15 Inconsistant member offset: 'name' The named structure member is multiply defined, and has a different offset from its first definition. 3.10.16 Inconsistant member type: 'name' The named structure member is multiply defined, and has a different type from its first definition. 3.10.17 Inconsistant re-declaration: 'name' You have attempted to redefine the named external symbol with a type which does not match its previously declared type. 3.10.18 Incorrect declaration A statement occuring outside of a function definition is not a valid declaration for a function or global variable. MICRO-C C-FLEA Compiler Page: 21 3.10.19 Invalid '&' operation You have attempted to reference the address of something that has no address. This error also occurs when you attempt to take the address of an array without giving it a full set of indicies. Since the address is already returned in this case, simply drop the '&'. (The error occurs because you are trying to take the address of an address). 3.10.20 Macro expansion too deep The compiler has encountered a nested macro reference which is too deep to be resolved. 3.10.21 Macro space exhausted The compiler has encountered more macro ("#define") text than it has room to store. 3.10.22 No active loop A "continue" or "break" statement was encountered when no loop is active. 3.10.23 No active switch A "case" or "default" statement was encountered when no "switch" statement is active. 3.10.24 Not an argument: 'name' You have declared the named variable as an argument, but it does not appear in the argument list. 3.10.25 Non-assignable You have attempted an operation which results in assignment of a value to an entity which cannot be assigned. (eg: 1 = 2); 3.10.26 Numeric constant required The compiler requires a constant expression which returns a simple numeric value. 3.10.27 String space exhausted The compiler has encountered more literal strings than it has room store. 3.10.28 Symbol table full The compiler has encountered more symbol definitions than it can handle. MICRO-C C-FLEA Compiler Page: 22 3.10.29 Syntax error The statement shown does not follow syntax rules and cannot be parsed. 3.10.30 Too many active cases The compiler has run out of space for storing switch/case tables. Reduce the number of active "cases". 3.10.31 Too many defines The compiler has encountered more '#define' statements than it can handle. Reduce the number of #defines. 3.10.32 Too many errors The compiler is aborting because of excessive errors. 3.10.33 Too many includes The compiler has encountered more nested "#include" files than it can handle. 3.10.34 Too many initializers You have specified more initialization values than there are locations in the global variable. 3.10.35 Type clash You have attempted to use a value in a manner which is inconsistant with its typing information. 3.10.36 Unable to open: 'name' A "#include" command specified the named file, which could not be opened. 3.10.37 Undefined: 'name' You have referenced a name which is not defined as a local or global symbol. 3.10.38 Unknown structure/member: 'name' You have referenced a structure template or member name which is not defined. 3.10.39 Unreferenced: 'name' The named symbol was defined as a local symbol in a function, but was never used in that function. This error will occur at the end of the function definition containing the symbol declaration. It is only a warning, and will not cause the compile to abort. MICRO-C C-FLEA Compiler Page: 23 3.10.40 Unresolved: 'name' The named symbol was forward referenced (Such as a GOTO label), and was never defined. This error will occur at the end of the function definition containing the reference. 3.10.41 Unterminated conditional The end of file was encountered when a "#if" or "#else" conditional block was being processed. 3.10.42 Unterminated function The end of the file was encountered when a function definition was still open. MICRO-C C-FLEA Compiler Page: 24 3.11 Quirks Due to its background as a highly compact and portable compiler, and its target application in embedded systems, MICRO-C deviates from standard 'C' in some areas. The following is a summary of the major infractions and quirks: When using the INTERNAL pre-processor, the operands to '#' commands are parsed based on separating spaces, and any portion of the line not required is ignored. In particular, the '#define' command only accepts a definition up to the next space or tab character. eg: #define APLUSONE A+1 <-- uses "A+1" #define APLUSONE A +1 <-- uses "A" Comments are stripped by the token scanner, which occurs AFTER the '#' commands are processed. eg: #define NULL /* comment */ <-- uses "/*" Note that since comments can therefore be included in "#define" symbols, you can use "/**/" to simulate spaces between tokens. eg: #define BYTE unsigned/**/char Include filenames are not delimited by '""' or '<>' and are passed to the operating system exactly as entered. eg: #include \mc\stdio.h NOTE: The above quirks DO NOT APPLY when the EXTERNAL pre-processor (MCP) is used. The appearance of a variable name in the argument list for a function declaration serves only to identify that variables location on the stack. MICRO-C will not define the variable unless it is explicitly declared (between the argument list and the main function body). In other words, all arguments to a function must be explicitly declared. MICRO-C is more strict about its handling of the ADDRESS operator ('&') than most other compilers. It will produce an error message if you attempt to take the address of a value which is already a fixed address (such as an array name without a full set of indicies). Since an address is already produced in such cases, simply drop the '&'. The 'x' in '0x' and '\x' is accepted in lower case only. MICRO-C C-FLEA Compiler Page: 25 When operating on pointers, MICRO-C only scales the increment (++), decrement (--) and index ([]) operations to account for the size of the pointer: eg: char *cptr; /* pointer to character */ int *iptr; /* pointer to integer */ ++cptr; /* Advance one character */ ++iptr; /* Advance one integer */ cptr[10]; /* Access the tenth character */ iptr[10]; /* Access the tenth integer */ cptr += 10; /* Advance 10 characters */ iptr += 10; /* Advance ONLY FIVE integers */ NOTE: A portable way to advance "iptr" by integers is: iptr = &iptr[10]; /* Advance 10 integers */ Since structures are internally represented as arrays of "char", incrementing a pointer to a structure will advance only one (1) byte in memory. To advance to the "next" instance of the structure, use: ptr += sizeof(struct template); The INDEXING operator '[]' is not commutative in MICRO-C. In other words 'array[index]' cannot be expressed as 'index[array]'. MICRO-C does not support "complex" declarations which use brackets '()' for other than function parameters. These are most often used in establishing pointers to functions: int (*a)(); /* Pointer to function returning INT */ (*a)(); /* Call address in 'a' */ Since MICRO-C allows you to call any value by following it with '()', you can get the desired effect in the above case, by declaring 'a' as a simple pointer to int, and calling it with the same syntax: int *a; /* Pointer to INT */ (*a)(); /* Call address in 'a' */ MICRO-C will not output external declarations to the output file for any variables or functions which are declared as "extern", unless that symbol is actually referenced in the 'C' source code. This prevents "extern" declarations in system header files (such as "stdio.h") which are used as prototypes for some library functions from causing those functions to be loaded into the object file. Therefore, any "extern" symbols which are referenced only by inline assembly code must be declared in the assembly code, not by the MICRO-C "extern" statement. MICRO-C C-FLEA Compiler Page: 26 Unlike some 'C' compilers, MICRO-C will process character expressions using only BYTE values. Character values are not promoted to INT unless there is an INT value involved in the expression. This results in much more efficent code when dealing with characters, particularily on small processors which have limited 16 bit instructions. Consider the statement: return c + 1; On some compilers, this will sign extend the character variable 'c' into an integer value, and then ADD an integer 1 and return the result. MICRO-C will ADD the character variable and a character 1, and then promote the result to INT before returning it (results of expressions as operands to 'return' are always promoted to int). Unfortunately, programs have been written which rely on the automatic promotion of characters to INTs to work properly. The most common source of problems is code which attempts to treat CHAR variables as UNSIGNED values (many older compilers did not support UNSIGNED CHAR). For example: return c & 255; In a compiler which always evaluates character expressions as INT, the above statement will extract the value of 'c' as positive integer ranging from 0 to 255. In MICRO-C, ANDing a character with 255 results in the same character, which gets promoted to an integer value ranging from -128 to 127. To force the promotion within the expression, you could CAST the variable to an INT: return (int)c & 255; The same objective can be achieved in a more efficent (and correct) manner by declaring the variable 'c' as UNSIGNED CHAR, or by CASTing the variable to an UNSIGNED value: return (unsigned)c; Note that this is not only more clearly shows the intent of the programmer, but also results is more efficent code generated. MICRO-C C-FLEA Compiler Page: 27 A related quirk arises because most processors do not support a simple efficent method for adding or subtracting a SIGNED 8 bit quantity and a 16 bit quantity. The code generators supplied with MICRO-C make the assumption that character values being added or subtracted to/from integers will contain only POSITIVE values, and thus use UNSIGNED addition/subtraction. This allows much more efficent code to be generated, as the carry/borrow from the low order byte of the operation is simply propagated to the high order byte of the result (an operation supported in hardware by the CPU). For those rare instances where you do wish to add/subtract a potentially negative character value to/from an int, you can force the expression to be performed in less efficent fully 16 bit arithmetic by casting the character to an int. int i; char c; ... i += c; /* Very efficent... C should be positive */ i += (int)c; /* Less efficent... C can be negative */ Read the notes at the end of the section entitled "Structures and Unions" for information on limitations or differences from standard 'C' in MICRO-C's implementation of structures and unions. MICRO-C C-FLEA Compiler Page: 28 4. ADVANCED TOPICS This section provides information on the more advanced aspects of MICRO-C, which is generally not needed for casual use of the language. 4.1 Conversion Rules MICRO-C keep track of the "type" of each value used in all expressions. This type identifies certain characteristics of the value, such as size range (8/16 bits), numeric scope (signed/unsigned), reference (value/pointer) etc. When an operation is performed on two values which have identical "types", MICRO-C assigns that same "type" to the result. When the two value "types" involved in an operation are different, MICRO-C calculates the "type" of the result using the following rules: 4.1.1 Size range If both values are direct (not pointer) references, the result will be 8 bits only if both values were 8 bits. If either value was 16 bits, the result will be 16 bits. If one value is a pointer, and the other is direct, the result will be a pointer to the same size value as the original pointer. If both values were pointers, the result will be a pointer to 16 bits only if both original pointers referenced 16 bit values. If either pointer referenced an 8 bit value, the result will reference an 8 bit value. 4.1.2 Numeric Scope The result of an expression is considered to be signed only if both original values were signed. If either value was an unsigned value, the result is unsigned. 4.1.3 Reference If either of the original values was a pointer, the result will be a pointer. Note that this "calculated" result type is used for partial results within an expression. Whenever a symbol such as a variable or function is referenced, the type of that symbol is taken from its declaration, no matter what "type" of value was last stored (variable) or returned (function). The TYPECAST operation may be used to override the type calculated for the result of an expression if necessary. MICRO-C C-FLEA Compiler Page: 29 4.2 Assembly Language Interface Assembly language programs may be called from 'C' functions and vice versa. These programs may be in the form of inline assembly language statements in the 'C' source code, or separately linked modules. INLINE code may use all virtual processor registers freely. Global variables defined in 'C' exist at absolute addresses and may be referenced directly by name from assembly language. Global names which are referenced by both assembly language and 'C' should not be longer than 15 characters. When MICRO-C calls any routine ('C' or assembler), it first pushes all arguments to the routine onto the processor stack, in the order in which they occur in the argument list to the function. This means that the LAST argument to the function is LOWEST on the processor stack. Arguments are always pushed as 16 bit values. Character values are extended to 16 bits, and arrays are passed as 16 bit pointers to the array. (MICRO-C knows that arrays which are arguments are actually pointers, and automatically references through the pointer). After pushing the arguments, MICRO-C then generates a machine language subroutine call, thereby executing the code of the routine. Once the called routine returns, the arguments are removed from the stack by the calling program. When the called function executes, the first thing usually done is to reserve space on the stack for any local variables which are required. MICRO-C C-FLEA Compiler Page: 30 It is the responsibility of the called function to remove any saved registers and local variable space from the stack before it returns. If a value is to be returned to the calling program, it is expected to be in the 16 bit ACCUMULATOR. Local variables in a function may be referenced as offsets from the stack pointer. Note that offsets must be adjusted for the number of additional bytes which are pushed and popped on the stack during the execution of the function. The address of a particular local variable is calculated as: "stack pointer" + (# bytes pushed during function execution) + (size of all preceeding local variables in bytes) Arguments to a function may also be referenced as direct offsets from the stack pointer, in much the same way as local variables are. The address of a particular argument is calculated as: "stack pointer" + (# bytes pushed during function execution) + (size of all local variables in bytes) + (Size of return address on stack (2)) + (# arguments from LAST argument) * 2 If a function has been declared as "register", MICRO-C will load the accumulator with the number of arguments which were passed, each time the function is called. This allows the function to determine the location of the first argument, which may be calculated as: "stack pointer" + (accumulator contents) * 2 + (# bytes pushed during function execution) + (size of all local variables in bytes) + (Size of return address on stack (2)) Examine the supplied library functions, as well as code produced by the compiler to gain more insight into the techniques of accessing local variables and arguments. MICRO-C C-FLEA Compiler Page: 31 4.3 Compiling for ROM The output from the compiler is entirely "clean", and may be placed in Read Only Memory (ROM). The compiler places all initialized global variables in the output file as part of the code image. When the program is stored in ROM, those variables are also stored in ROM, and will not be modifiable. When the program is to be placed in ROM, you may not initialize any variables which you intend to modify later. Those variables must be explicitly initialized by code executed at the beginning of the program. Variables which you do not intend to modify (such as tables etc.) may be initialized in the declaration, and will be permanently saved in the ROM as part of the static code image. The addresses for code and data storage are established by the startup files in the runtime library, You may examine and modify these files to suit your own particular memory allocation needs. MICRO-C C-FLEA Compiler Page: 32 5. THE MICRO-C COMPILER The heart of the MICRO-C programming environment is the COMPILER. This program reads a file containing a 'C' source program, and translates it into an equivalent assembly language program. The compiler includes its own limited pre-processor, which is suitable for compiling programs requiring only non-parameterized MACRO substitution, simple INCLUDE file capability, and single-level CONDITIONAL processing. 5.1 The MCCCF command The format of the MICRO-C C-FLEA Compiler command line is: MCCCF [input_file] [output_file] [options] [input_file] is the name of the source file containing 'C' statements to read. If no filenames are given, MCCCF will read from standard input. [output_file] is the name of the file to which the generated assembly language code is written. If less than two filenames are specified, MCCCF will write to standard output. 5.1.1 Command Line Options -c - Includes the 'C' source code in the output file as assembly language comments. -f - Causes the compiler to "Fold" its literal pool. (Identical strings not contained in explicit variables only once in memory). -l - Enables MCCCF to accept line numbers. (At beginning of line, followed by ':'). -q - Instructs MCCCF to be quiet, and not display the startup message when it is executed. MICRO-C C-FLEA Compiler Page: 33 6. THE MICRO-C PREPROCESSOR The MICRO-C Preprocessor is a source code filter, which provides greater capabilities than the preprocessor which is integral to the MICRO-C compiler. It has been implemented as a stand alone utility program which processes the source code before it is compiled. Due to the higher complexity of this preprocessor, it operates slightly slower than the the integral MICRO-C preprocessor. This is mainly due to the fact that it reads each line from the file and then copies it to a new line while performing the macro substitution. This is necessary since each macro may contain parameters which must be replaced "on the fly" when it is referenced. The integral MICRO-C preprocessor is very FAST, because it does not copy the input line. When it encounters a '#define'd symbol, it simply adjusts the input scanner pointer to point to the definition of that symbol. Keeping the extended preprocessor as a stand alone utility allows you to choose between greater MACRO capability and faster compilation. It also allows the system to continue to run on very small hardware platforms. The additional capabilities of the extended preprocessor are: - Parameterized MACROs. - Multiple line MACRO's. - Nested conditionals. - Ability to undefine MACRO symbols. - Library reference in include file names. MICRO-C C-FLEA Compiler Page: 34 6.1 The MCP command The format of the MICRO-C Preprocessor command line is: MCP [input_file] [output_file] [options] [input_file] is the name of the source file containing 'C' statements to read. If no filenames are given, MCP will read from standard input. [output_file] is the name of the file to which the processed source code is written. If less than two filenames are specified, MCP will write to standard output. 6.1.1 Command Line Options MCP accepts the following command line [options]: -c - Instructs MCP to keep comments from the input file (except for those in '#' statements which are always removed). Normally, MCP will remove all comments. -l - Causes the output file to contain line numbers. Each line in the output file will be prefixed with the line number of the originating line from the input file. l=path - Defines the directory path which will be taken to reference "library" files when '<>' are used around an '#include' file name. Unless otherwise specified, the path defaults to: '\mc' -q - Instructs MCP to be quiet, and not display the startup message when it is executed. <name>=<text> - Pre-defines a non-parameterized macro of the specified <name> with the string value <text>. MICRO-C C-FLEA Compiler Page: 35 6.2 Preprocesor Commands The following commands are recognized by the MCP utility, only if they occur at the beginning of the source file line: 6.2.1 #define <name>(parameters) <replacement text> Defines a global macro name which will be replaced with the indicated <replacement text> wherever it occurs in the source file. Macro names may be any length, and may contain the characters 'a'-'z', 'A'-'Z', '0'-'9' and '_'. Names must not begin with the characters '0'-'9'. If the macro name is IMMEDIATELY followed by a list of up to 10 parameter names contained in brackets, those parameter names will be substituted with parameters passed to the macro when it is referenced. Parameter names follow the same rules as macro names. eg: #define min(a, b) (a < b ? a : b) If any spaces exist between the macro name and the opening '(', the macro will not be parameterized, and all following text (including '(' and ')') will be entered into the macro definition. If the very last character of a macro definition line is '\', MCP will continue the definition with the next line (The '\' is not included). Pre-processor statements included as part of a macro definition will not be processed by MCP, but will be passed on and handled by the integral MICRO-C preprocessor. 6.2.2 #undef <symbol> Undefines the named macro symbol. further references to this symbol will not be replaced. NOTE: With MCP, macro definitions operate on a STACK. IE: If you define a macro symbol, and then re-define it (without '#undef'ing it first), subsequently '#undef'ing it will cause it to revert to its previous definition. A second '#undef' would then cause it to be completely undefined. MICRO-C C-FLEA Compiler Page: 36 6.2.3 #forget <symbol> Similar to '#undef', except that the symbol and ALL SUBSEQUENTLY DEFINED SYMBOLS will be undefined. Useful for releasing any local symbols (used only within a single include file). For example: #define GLOBAL "xxx" /* first global symbol */ ... /* more globals */ #define LOCAL "xxx" /* first local symbol */ ... /* more locals */ /* body of include file goes here */ #forget LOCAL /* release locals */ 6.2.4 #ifdef <symbol> Causes the following lines (up to '#else' of '#endif') to be processed and included in the source file only if the named symbol is defined as a macro. 6.2.5 #ifndef <symbol> Causes the following lines (up to '#else' of '#endif') to be processed and included in the source file only if the named symbol is NOT defined as a macro. NOTE: '#ifdef/#ifndef#else/#endif' may be nested. 6.2.6 #else Toggles the state of the "if_flag", controlling conditional processing. Only has effect in the highest level of suspended processing. IE: Nested conditionals will work properly. If the previous '#ifdef/#ifndef' failed, processing will begin again following the '#else'. If the previous '#ifdef/#ifndef' passed, processing will be suspended until the '#endif' is encountered. NOTE: Since '#else' acts as a toggle, it may be used outside of any '#ifdef/#ifndef' to unconditionally suspend processing up to '#endif'. You can also use multiple '#else's in a single conditional, to swap back and forth between true/false processing without re-testing the condition. 6.2.7 #endif Resets the "if_flag" controlling conditionals, causing processing to resume. Only has effect in the highest level of suspended processing. IE: Nested conditionals will work properly. MICRO-C C-FLEA Compiler Page: 37 6.2.8 #include <filename> Causes MCP to open the named file and include its contents as part of the input source. If the filename is contained within '"' characters, it will be opened exactly as specified, and (unless it contains a directory path) will reference a file in the current directory. If the filename is contained within the characters '<' and '>', it will be prefixed with the library path (See 'l=' option), and will therefore reference a file in that library directory. The default library directory is assumed to be '\mc'. For example: #include "header.h" /* from current directory */ #include <stdio.h> /* from library directory */ MICRO-C C-FLEA Compiler Page: 38 6.3 Error messages When MCP detects an error during processing of an include file, it displays an error message, which is preceeded by the filename and line number where the error occurs. If more than 10 errors are encountered, MCP will terminate. The following error messages are reported by MCP: 6.3.1 Cannot open include file A '#include' statement on the indicated line specified a file which could not be opened for reading. 6.3.2 Invalid include file name A '#include' statement on the indicated line specified a file name which was not contained within '"' or '<>' characters. 6.3.3 Invalid macro name A '#define' statement on the indicated line contains a macro name which does not follow the name rules. 6.3.4 Invalid macro parameter A '#define' statement on the indicated line contains a macro parameter name which does not follow the name rules. A reference to a macro does not have a proper ')' character to terminate the parameter list. 6.3.5 Too many errors More than 10 errors has been encountered and MCP is terminating. 6.3.6 Too many macro definitions MCP has encountered more '#define' statements than it can handle. 6.3.7 Too many macro parameters A '#define' statement on the indicated line specifies more parameters to the macro than MCP can handle. 6.3.8 Too many include files MCP has encountered more nested '#include' statements than it can handle. MICRO-C C-FLEA Compiler Page: 39 6.3.9 Undefined macro A '#undef' or '#forget' statement on the indicated line references a macro name which has not been defined. 6.3.10 Unterminated comment The END OF FILE has been encountered while processing a comment. 6.3.11 Unterminated string A quoted string on the indicated line has no end. To continue a string to the next line, use '\' as the last character on the line. The '\' will not be included in the string. MICRO-C C-FLEA Compiler Page: 40 7. THE MICRO-C OPTIMIZER The MICRO-C optimizer is an output code filter which examines the assembly code produced by the compiler, recognizing known patterns of inefficent code (using the "peephole" technique), and replaces them with more optimal code which performs the same function. It is entirely table driven, allowing it to be modified for virtually any processor. Due its many table lookup operations, the optimizer may perform quite slowly when processing a large file. For this reason, most people prefer not to optimize during the debugging of a program, and utilize the optimizer only when creating the final copy. 7.1 The MCOCF command The format of the MICRO-C Optimizer command line is: MCOCF [input_file] [output_file] [options] [input_file] is the name of the source file containing assembly statements to read. If no filenames are given, MCOCF will read from standard input. [output_file] is the name of the file to which the optimized assembly code is written. If less than two filenames are specified, MCOCF will write to standard output. 7.1.1 Command Line Options MCOCF accepts the following command line [options]: -d - Instructs MCOCF to produce a 'debug' display on standard output showing the source code which it is removing and replacing in the input file. NOTE: If you do not specify an explict output file, you will get the debug statements intermixed with the optimized code on standard output. -q - Instructs MCOCF to be quiet, and not display the startup message when it is executed. MICRO-C C-FLEA Compiler Page: 41 8. THE SOURCE LINKER Many small development environments have assemblers which do not directly support an object linker. This causes a problem with 'C' development, because the library functions must be included in the source code, with several drawbacks: 1) There is no way to automatically tell which library functions to include, therefore, you must do it manually. 2) 'C' library functions must be re-compiled every time, in order to avoid conflict between compiler generated labels. The MICRO-C Source Linker (SLINK) helps overcome these problems, by automatically joining previously compiled (assembly language) source code from the library to your programs. Only those files containing functions which you reference are joined (Taking into consideration functions called by the included library functions etc...). As the files are joined, compiler generated labels are adjusted to be unique within each file. 8.1 The SLINK Command The format of the SLINK command line is: SLINK input_file... output_file [options] "input_file" is the name of the source file containing the compiler output from your program. Several input files may be specified, in which case they will all be processed into a single output file. "output_file" is the name of the file to which the linked source code is written. MICRO-C C-FLEA Compiler Page: 42 8.1.1 Command line options SLINK accepts the following command line [options]: ? - Display command line help summary. i=name - Specify name of the External Index File. -l - Instructs SLINK to list each library used. l=path - Identifies the directory path which will be taken to reference "library" files. If not specified, it defaults to: '\mc\slib' p=char - Identifies the PREFIX character of compiler generated symbols. Defaults is '?'. -q - Inhibit display of the startup message. t=string- Prefix to prepend to temporary filenames. If not specified, default is "$". -w - Sort WORD data to beginning of allocated bulk unitialized storage (See $DD: directive). 8.2 Multiple Input Files SLINK accepts multiple input files on the command line, and processes each file to build the output file. This allows you to "link" together several previously compiled (or assembly language) modules into one final program. Any external references which are not resolvable from the library are assumed to be resolved by one of the input source files. Since SLINK does not have knowledge of the public symbols defined in the input files, the absence of an externally referenced symbol will not be detected until the assembly step (where it will cause an undefined symbol error). MICRO-C C-FLEA Compiler Page: 43 8.3 The External Index File SLINK uses a special file from the library to determine which symbols are in which files. This files is called the EXTERNAL INDEX FILE, and is found in the library directory (see 'l=' option), under the name "EXTINDEX.LIB". This file contains entries which cross-reference external symbols to files. Each entry is as follows: 1) Any lines beginning with '<' contain the names of files which are to be processed and included at the BEGINNING of the program (Before your source file). This the best way to include the startup code and any runtime library routines which are required at all times, and also provides a method of initializing any segments used. eg: <6809rl.asm 2) Any lines beginning with '^' contain the names of files which are to be processed AFTER the program and library source files, but BEFORE any uninitialized data areas are output. This is the best way to set up the location and storage class of the uninitialized data if it does not immediately follow the executable program code, and also providing any postamble needed by the segments. 3) Any lines beginning with '>' contain the names of files which are to be processed at the END of the program, after all other information is output. This is the best way to define heap memory storage, and to provide any post-amble needed by the assembler. 4) Any lines beginning with '-' contain the names of files which are to be included if any of the following symbols (Up to another '<', '^', '>', '-' or '$') are referenced. eg: -printf.asm format.asm fgets.asm fget.asm NOTE: In most cases, the library functions will contain indications of any external references that they do, in which case SLINK will automatically include those files even of the names are not mentioned on the '-' line. In the example above, the following would suffice: -printf.asm 5) The names of each symbol which may be referenced externally must follow the '<', '^', '>' or '-' entry. Symbols must occur one per line, with no leading or trailing spaces. eg: printf fprintf sprintf MICRO-C C-FLEA Compiler Page: 44 6) A line beginning with '$' is used to define the pseudo- opcode used by SLINK to reserve uninitialized data at the end of the output file. Only one line beginning with '$' should be entered into the EXTINDEX.LIB file. The remainder of this line, including all spaces etc. is entered between each symbol name, and the decimal size (in bytes) which is written to the output file. eg: '$ RMB ' <- Quotes are for clarity A complete example: -printf.asm printf fprintf sprintf -scanf.asm scanf fscanf sscanf <PREFIX.asm ^MIDDLE.ASM >SUFFIX.ASM $ RMB In summary, the output file is written from: 1 - The '<' (prefix) files * 2 - The program source files *\ 3 - Library files referenced (if any) * > See note 4 - Segments 1-9 from above ... */ 5 - The '^' (middle) files 6 - Segments 1-9 from middle files * See note 7 - Uninitialized data definitions (if any) 8 - The '>' (suffix) files 9 - Segments 1-9 from sufix file(s) * See note * NOTE: If these files contain multiple segments (see later), all segments are grouped and written in seguential order. IE: Seg 0 from all files is written, followed by Seg 1, etc. MICRO-C C-FLEA Compiler Page: 45 8.4 Source file information 8.4.1 SLINK Directives SLINK interpretes several "directives" which may be inserted in the input source files to control the source linking process. These directives must be on a separate line, beginning in column 1, and must be in uppercase. They are removed by SLINK during processing, and thus will not cause conflict with the normal syntax used by the assembler. $SE:<0-9> The '$SE' directive is used by SLINK to define multiple output segments. Up to 10 segments are allowed, with segment 0 being the default which is selected when a file is first encountered. Other segments (1-9) when selected via this directive are written to temporary files, and re-joined at the end of processing in sequential order. this allows you to separate sections of the source file (such as initialized data, literal pool etc.) into distinct areas of memory. $DD:<symbol> <size> The '$DD' directive is used to define uninitialized data storage areas, which will be allocated by SLINK between the '^' (middle) and '>' (suffix) files. This allows you to allocate unitialized data outside of the bounds of the executable image, and thus exclude it from being saved to disk. This action may be thought of as an additional (11'th) segment which is available for uninitialized data only, and which avoids the temporary file read/write overhead associated with use of the other segments. This directive is normally placed into the source file by the "def_global" routine in the MICRO-C code generator. $EX:<symbol> The '$EX' directuve is used by SLINK to identify any symbols which are externally referenced. Whenever a '$EX' directive is found, SLINK searches the EXTINDX.LIB file for the named symbol, and marks the corresponding files for inclusion in the program. This directive is normally placed into the source file by the "def_extern" routine in the MICRO-C code generator. If you are writing assembly language programs for the library, be sure to include "$SE:<0-9>" directives for any segments you wish to access, "$DD:<symbol> <size>" directives for any uninitialized data you wish to allocate, and "$EX:<symbol>" directives for any symbols which you externally reference. If you wish to place an assembly language comment on the same line, make sure it is separated from the remainder of the directive by at least one space or tab character. MICRO-C C-FLEA Compiler Page: 46 Also, note that '<' (prefix) files may contain "$SE", "$DD" and "$EX" directives, '^' (middle) files may contain "$SE" and "$DD" but not "$EX", and '>' (suffix) files may only contains "$SE" directives. Basically, the rule is that "$EX" cannot be used after the libraries are included and "$DD" cannot be used after the uninitialized data is output. Since the middle and suffix files are ALWAYS included, simply insure that all external references and data declarations needed by any of them are performed in the '<' (prefix) file. 8.4.2 Compiler generated labels As it processes each source file, SLINK scans each line for symbols which consist of the '?' character (See 'p=' option), followed by a number. If it finds such as symbol, it inserts a two character sequence ranging from 'AA' to 'ZZ' between the '?', and the number. This sequence will be incremented for each source file processed, and thus insures that the compiler generated symbols will be unique for each file. If you are writing assembly language programs for the library, you must be careful to avoid using identical local symbols in any of the library files, one way to do this is to use symbols which meet the above criteria. 8.5 The SCONVERT command SCONVERT is a utility which assists in converting existing assembly language source files into a format which is more suitable for use by the SLINK. Two main functions are performed: 1) All comments are removed, and all spacing is reduced to a single space. This minimizes the size of the file, and helps decrease linkage time. 2) All symbols defined in the file which are not identified as "keep" symbols are converted to resemble the MICRO-C compiler generated symbols. This allows SLINK to adjust them to be unique within each source file. The format of the SCONVERT command line is: SCONVERT [input_file] [output_file] [options] [input_file] is the name of the source file containing the original assembly language program. If no filenames is given, SCONVERT will read from standard input. [output_file] is the name of the file to which the converted source code is written. If less that two filenames are given, SCONVERT will write to standard output. MICRO-C C-FLEA Compiler Page: 47 8.5.1 Command line options SCONVERT accepts the following command line [options]: ? - Display command line help summary. c=char - Identifies the character used to begin a comment at the trailing end of a source line. If no 'c=' is defined, SCONVERT will terminate processing at the first blank or tab which follows the operand field. C=char - Identifies the charcter which indicates a comment line in the source code. Defaults to '*'. k=name - Identifies a symbol name to KEEP. This symbol will not be converted. Multiple 'k=' are permitted. K=file - Identifies a file containing the names of symbols to KEEP, one per line. Multiple 'K=' are permitted. p=char - Identifies the PREFIX character which is to be used for the converted symbols. Defaults to '?'. -q - Instructs SCONVERT to be quiet, and not issue its startup message. SCONVERT identifies symbols in the input source file as any string beginning with 'A-Z', 'a-z', '_' or '?', and containing these charcters plus the digits '0-9'. If your assembler source files uses any other characters in its symbols, you must edit your sources and change the symbols. 8.6 The SRENUM command SRENUM is a small utility which re-numbers the compiler generated symbols within a assembly language source file. This is useful if you have made added symbols to the file by hand, and wish to make it "pretty" before adding it to the library etc. The format of the SRENUM command is: SRENUM [input_file] [output_file] [options] 8.6.1 Command line options SRENUM accepts the following command line [options]: ? - Display command line help summary. p=char - Identifies the PREFIX character which is to be used to recognize compiler generated symbols. -q - Instructs SRENUM to be quiet, and not issue its startup message. MICRO-C C-FLEA Compiler Page: 48 8.7 The SINDEX command SINDEX is a utility which assists in the creation of the EXTINDEX.LIB file used by SLINK. When you run SINDEX, it examines all of the '.ASM' files in the current directory, and writes a EXTINDEX.LIB file which contains a '-' type entry for each file, and external symbol entries for any labels which it finds conforming to the 'C' naming conventions (Starts with 'a-z', 'A-Z' or '_', and contains only 'a-z', 'A-Z', '0-9' or '_'). Once you have run SINDEX, you must manually edit the EXTINDEX.LIB file, and remove any file or symbol entries which you do not wish to have available as external references, as well as insert any necessary entries for '<', '^', '>' and '$' commands. 8.7.1 Command line options SINDEX accepts the following command line options: ? - Display command line help summary. i=name - Specify name for index file to be written. Dafault is "EXTINDEX.LIB". You may also instruct SINDEX to search for a file pattern other than '*.ASM' by passing it as a command line parameter. eg: SINDEX *.ACF 8.8 The SLIB command Once you have constructed your source library, you may from time to time want to make minor changes to it, either adding new functions, or removing old ones ones. You could make such changes simply by editing the EXTINDEX.LIB file, however you would have to be very careful not to add or delete the wrong entry, and you would have to manually determine if adding or removing the file would adversly affect the remainder of the library. For example, you could accidently add a duplicate of another symbol name, or remove a symbol which is referred to by another file. To simplify maintenance of source libraries, you can make use of the "Source Librarian", a utility program which automates the addition and removal of source files, and automatically reports of any inconsistancies occuring in the source library. To use SLIB, you must first position yourself to the directory containing the source library. And then execute SLIB using the command options described later to indicate the action to be taken on the library. If you do not specify any actions, SLIB will simply examine the library and report its size and content. MICRO-C C-FLEA Compiler Page: 49 You may use multiple command options in a single SLIB command if you wish to add and/or remove more than one file at a time. After executing any command, SLIB will report on any inconsistancies which it finds in the library. If any are found, and you have used a command which caused changes, SLIB will prompt for permission before writing the updated library file. 8.8.1 Command line options The following options control the action(s) which will be performed by SLIB on the source library index file. ? - Display command line help summary. ?=file - Display information about named source file. a=file - Add specified file as standard functions. i=index - Use the specified INDEX file, if not specified, the filename 'EXTINDEX.LIB' is assumed. m=file - Add named source file as a MIDDLE file. p=file - Add named source file as a PREFIX file. -q - Quiet mode: SLIB will not display informational messages or ask for permission to update index. r=file - Remove the named file from the index. s=file - Add named source file as a SUFFIX file. -w - Write inhibit: SLIB will not write the updated library index. This is useful if you just want to see what would happen if you add or remove a file. MICRO-C C-FLEA Compiler Page: 50 8.9 Making a source library To make a complete source linkable library, follow these basic steps: 1) If you have assembly language library functions, run the SINDEX utility to create an index file with the names of any symbols defined in them. Edit this file and remove all names which are LOCAL to the files. Only the global function and variable names should remain. NOTE: Also leave in any other symbols or names which you don't want changed by SCONVERT. 2) Use SCONVERT to convert the assembly language sources into library format, using the index file created above as your KEEP file (K=EXTINDEX.LIB). You may send the output files directly to your source library directory. 3) Edit the converted assembly language sources to change any declarations for uninitialized data into '$DD' directives, and to add any '$SE' and '$EX' directives which may be needed. 4) Compile all of your 'C' library functions to assembly language, using a code generator which outputs the appropriate directives for SLINK. Send the ASM output files to your source library directory. 5) From within your library directory, run the SINDEX utility again. This will create an index file (EXTINDEX.LIB) which contains the names of all global symbols. 6) Edit the index file and remove any non-public symbol names. You should also change the headers for the '<', '^' and '>' files, and add the '$' record for reserved memory information. 7) Run the SLIB utility, to check the new library for duplicate symbols, unresolved external references and any other inconsistancies. MICRO-C C-FLEA Compiler Page: 51 9. THE MAKE UTILITY The MAKE utility provides a method of automating the building of larger programs consisting of more that one module. The main benefit of MAKE is that it keeps track of the files that each module is dependant on, and will rebuild a module if any of those files have been modified since the module was last built. This frees the programmer from the task of remembering which files have been changed, and the commands needed to rebuild the dependant modules. 9.1 MAKEfiles To use MAKE, you must first create a MAKEFILE, which is a text file containing entries for each module in the program. Each entry consists of a DEPENDANCY list, and a series of COMMANDS. 9.1.1 MAKEfile Entries A dependency list in MAKE is a line which contains the name of the module, followed by a ':', followed by the names of any files on which it depends. The module name MUST begin in column 1. When MAKE is invoked, it will process each dependancy list, and will execute any following commands (up to another dependancy list) if (1) the module does not exist, or (2) if any of the files to the right of the ':' have a timestamp which is later than that of the module. For example: main.asm : main.c main.h \\mc\\stdio.h \\mc\\mccCF main.c main.tmp \\mc\\mcoCF main.tmp main.asm -del main.tmp In the above example, the 'main.asm' would be rebuilt (by compiling and optimizing 'main.c') if either it did not already exist, or any of 'main.c', 'main.h' or '\mc\stdio.h' was found to have a later timestamp. The '-' preceeding the 'del' command prevents it from being displayed. Unless the '-q' option is enabled, MAKE will display any commands not preceeded by '-' as they are executed. NOTE: To enter a single '\' in the MAKEFILE, you must use '\\', this is because like 'C', MAKE uses '\' to "protect" special characters which otherwise are used for special functions (such as '\', '$' and '#'). The first '\' "protects" the second one, allowing it to pass through as source text. MICRO-C C-FLEA Compiler Page: 52 9.1.2 Macro Substitutions Sometimes in a MAKEFILE, you have a single file or directory path that you use over and over again. If it is a long directory path, this may involve a lot of typing, and it becomes inconvenient to change that name (if you want to use a different directory etc.) because it is repeated many times. MAKE includes a MACRO facility, which allows you to define variable names which will be replaced with a text string when used in subsequent MAKEfile lines. Names are defined by placing them in the MAKEfile, followed by '=', and the text string. Macro names being defined MUST begin in column one, and may consist of the characters ('a'-'z', 'A'-'Z', '0'-'9', and '_'). Whenever MAKE encounters a '$' in the file, it takes the name immediately following, and performs the macro replacement: mcdir = \\mc main.asm : main.c main.h $mcdir\\stdio.h $mcdir\\mccCF main.c main.tmp $mcdir\\mcoCF main.tmp main.asm del main.tmp When a macro name is immediately followed by alphanumeric text, use a single '\' to separate it from the text. This "protects" the first character of the text from being interpreted as part of the macro name: mcdir = \\mc\\ main.asm : main.c main.h $mcdir\stdio.h $mcdir\mccCF main.c main.tmp $mcdir\mcoCF main.tmp main.asm del main.tmp There are several predefined macro symbols which are available: $* = The full name of the dependant module (name.type). $@ = The name only of the dependant module. $. = The full name of each file in the dependancy list, separated from each other by a single space. $, = The full name of each file in the dependancy list, separated from each other by a single comma. $: = The name only of each file in the dependancy list, separated from each other by a single space. $; = The name only of each file in the dependancy list, separated from each other by a single comma. MICRO-C C-FLEA Compiler Page: 53 File names in the dependancy list which are preceeded by '-' will not be included in the '$. $, $: $;' macro expansions: mcdir = \\mc main.asm : main.c -main.h -$mcdir\\stdio.h $mcdir\\mccCF $. $@.TMP $mcdir\\mcoCF $@.TMP $* del $@.TMP 9.1.3 MAKEfile Comments Whenever MAKE encounters the '#' character in the MAKEFILE, it treats the remainder of the line as a comment, and does not process it: # Define Directories mcdir = \\mc # Build the MAIN module main.asm : main.c -main.h -$mcdir\\stdio.h # Dependants $mcdir\\mccCF $. $@.TMP # Compile $mcdir\\mcoCF $@.TMP $* # Optimize del $@.TMP # Delete tmp 9.1.4 Ordering the MAKEfile MAKE processes the MAKEfile is sequential fashion, with the entries near the top being processed before the entries near the bottom. To insure that each module is built properly, any files appearing in the dependancy list for a module which are themselves dependant on other files, should have MAKEfile entries which occur BEFORE the entries for the modules which are dependant on them: # Define Directories mcdir = \\mc # Build the MAIN module main.asm : main.c -main.h -$mcdir\\stdio.h $mcdir\\mccCF $. $@.TMP $mcdir\\mcoCF $@.TMP $* del $@.TMP # Build the SUB module sub.asm : sub.c -sub.h $mcdir\\mccCF $. $@.TMP $mcdir\\mcoCF $@.TMP $* del $@.TMP # Link the final file & generate listing # NOTE: If either of the above modules is rebuilt, # this entry will be guarenteed to execute. prog.hex : main.asm sub.asm $mcdir\\slink $. $@.asm l=\mc\libCF $mcdir\\asmCF $@ -fs MICRO-C C-FLEA Compiler Page: 54 9.2 Directives Like 'C', MAKE recognizes several "directives" in the MAKEfile. These directives are only recognized if they occur at the beginning of the input line: 9.2.1 @include <filename> This command causes the indicated file to be opened and read in as the source text. When the end of the new file is encountered, processing will continue with the line following "@include" in the original MAKEfile. 9.2.2 @ifdef <name> [name...] Processes the following lines (up to @else of @endif) only if one of the given MACRO names is defined. NOTE: <name> should not be preceeded by '$', otherwise its CONTENTS will be tested. 9.2.3 @ifndef <name> [name...] Processes the following lines (up to @else of @endif) only if one of the given MACRO name is NOT defined. 9.2.4 @ifeq <word1> <word2> [word3...] Processes the following lines (up to @else of @endif) only if the first word matches one of the remaining words exactly. This is useful for testing the value of a defined MACRO symbol. 9.2.5 @ifne <word1> <word2> Processes the following lines (up to @else or @endif) only if the first word does not match any of the following words. 9.2.6 @else Processes the following lines (up to @endif) only if the preceeding @ifdef, @ifndef, @ifeq or @ifne was false. 9.2.7 @endif Terminates @ifdef, @ifndef, @ifeq and @ifne. 9.2.8 @type <text> Displays the following text. 9.2.9 @abort [text] Terminates MAKE with an 'Aborted!' message. Any text on the remainder of the line will be appended to the message. MICRO-C C-FLEA Compiler Page: 55 9.3 The MAKE command The format of the MAKE command line is: MAKE [makefile] [options] [makefile] is the name of the MAKEfile to process. If no name is given, MAKE assumes the default name 'MAKEFILE'. 9.3.1 Command Line Options MAKE accepts the following command line [options]: ? - Causes MAKE to output a short summary of the available command line options. -d - Instructs MAKE to operate in "debug" mode, and display the commands which it would execute, without actually executing them. This provides a method of quickly testing the MAKEFILE. -q - Instructs MAKE to be quiet, and not display the informational messages and commands executed as it progresses. <name>=<text> - Pre-defines a macro of the specified <name> with the string value <text>. This OVERRIDES any definition within the MAKEfile, which may be used to establish a "default" value. MICRO-C C-FLEA Compiler Page: 56 9.4 The TOUCH command TOUCH is a small utility program which sets the timestamp of one or more files to the current or specified time/date. It is useful as a method of forcing MAKE to recognize a file as "changed", even when it has not. For example, if you had decided to "undo" several recent changes by restoring a backup of 'main.c', the restored file will probably have a timestamp which is older than the last module which was built. In this case, MAKE would be unaware that the file has changed, and would therefore not rebuild the module. The TOUCH command could then be used to "update" the timestamp of 'main.c' to the current time, causing MAKE to recognize it as a changed file. TOUCH main.c You could also use TOUCH to force rebuilding of several files: TOUCH main.c sub1.c sub2.c Or even ALL '.C' files: TOUCH *.c TOUCH can also be used to set the timestamp of a file to an arbritrary value, this may be useful to PREVENT a change from causing an update: TOUCH main.c t=0:00 d=31/10/80 NOTE: Use of the 't=' or 'd=' parameters to TOUCH allows the possibility that a changed file will go unnoticed. CAUTION is advised. The MSDOS implementation of TOUCH supports '-h' and '-s' options, which cause it to set the timestamp of HIDDEN and/or SYSTEM files. If these options are not used, TOUCH will not affect those types of files. MICRO-C C-FLEA Compiler Page: 57 10. EDT - Text editor 10.1 Introduction EDT is a fully featured, in-memory, text editor, which is suitable for entry and editing of MICRO-C and ASM source programs. It operates in either a line-by-line, or a visual screen format. In line-by-line mode, EDT performs no direct screen accesses, and may be operated over a serial port using CTTY. EDT is invoked with the command 'EDT <filename>'. If the named file already exists, EDT will load and edit it, otherwise a blank file is presented. If the optional '-v' qualifier is specified, EDT will start-up in line-by-line mode, otherwise it starts up in visual mode. eg: edt thefile.dat <- Visual mode edt myfile.dat -v <- Line by Line 10.2 Line mode operation 10.2.1 Line ranges Most commands accept a "line-range" which is an optional specification controlling the range of lines for which the command has effect. Unless otherwise stated, the default line-range assumed for each command is the "current" line (*). The "current" line is the line at which EDT is positioned in line by line mode, and is also the line on which the cursor is positioned in visual mode. The following are the valid line range formats: * - The "current" line / - The entire file = - The tagged lines 0 - The end of the file <n> - Line number <n>, (<n> >= 1) <r>,<r> - Range between beginning of two other ranges. The '+' and '-' characters may be used to add or subtract a constant value from a line range. eg: '0-12' <- 12 lines from end of file If '+' or '-' is used but no range is specified, an offset from the current line is assumed. eg: '+12' <- 12 lines from the current line. The line range specification is entered immediately preceeding the command name. ie: '<r><command> <operands>' MICRO-C C-FLEA Compiler Page: 58 10.2.2 Line mode commands C - Copy text The 'C'opy command performs a copy of the active range of lines, placeing the copy directly ahead of the current line. Examples: C - Duplicate current line 1,10C - Copy lines 1 to 10 inclusive =C - Copy tagged lines /C - Duplicate entire file (must be at end) D - Delete text The 'D'elete command deletes the active range of lines. Examples: D - Delete current line -5,+5D - Delete 11 lines -5 to +5 from current /D - Delete entire file F - File information This command displays information about the file being edited, includes the filename, the size of the file in lines and characters, and the size and position of the specified line range. Examples: F - Display file & current line information =F - Display file & tagged lines information I - Insert new text The 'I'nsert command prompts for 'Input:', and inserts all lines typed directly ahead of the active range. Enter a null line to exit. Examples: I - Insert ahead of current line /I - Insert at start of file 0I - Insert at end of file MICRO-C C-FLEA Compiler Page: 59 L - List text in simple form The 'L'ist command displays the active range of lines. The display does not include line numbers or special indications. 'L'ist is faster and mode efficent that 'P'rint. Examples: L - List current line /L - List entire file -10,+10L - List 21 lines, centered on current M - Move text The 'M'ove command moves the active range of lines to the location directly ahead of the current line. Examples: =M - Move tagged lines +1M - Interchange active & next line P - Print text (Enhanced 'L'ist) The 'P'rint command displays the active range of lines. This display includes the line number which may be preceded by a special indication flag ('*' for current line, '=' for tagged lines). Examples: P - Display current line /P - Display entire file Q - Quit (exit) editor The 'Q'uit command exits the editor. This command will not allow an exit if unsaved changes are present in the file. Examples: Q - Quit editor QQ - Unconditional 'Q'uit The 'QQ'uit command exits the editor unconditionaly. Examples: QQ - Quit unconditionaly. MICRO-C C-FLEA Compiler Page: 60 R <filename> - Read file The 'R'ead command reads the entire contents of the specified file, and inserts it directly ahead of the active range. Examples: Rabc - Insert file 'abc' at current /Rabc - Insert file 'abc' at start 0Rabc - Append file 'abc' at end S<dc><search><dc><replace> - Substitute The 'S'ubstitute command searches the active range of lines, and replaces all occurrances of the string <search> with the string <replace>. The <dc> delimiter character may be any character not contained within the <search> string. Examples: S'abc'def - Change 'abc' to 'def' in current /S'abc'def - Change 'abc' to 'def' in entire file =S'abc'def - Change 'abc' to 'def' in tagged lines T - Tag lines The 'T'ag command tags the active range of lines, allowing them to be referred to by '=' in a subsequent command range. Examples: T - Tag current line 1,10T - Tag lines 1 to 10 *,+5T - Tag six lines starting at current V - Switch Visual Mode The 'V' command causes EDT to switch visual modes. This enters visual mode if EDT was previously in line by line mode, and enters line by line mode if previously in visual mode. Examples: V - Switch visual modes MICRO-C C-FLEA Compiler Page: 61 W [filename] - Write to file The 'W' command writes the active range of lines to the named file, or to the original file edited if no name is specified. Use of this command also resets the FILE CHANGED flag, allowing exit via 'q'. The default line range assumed for 'W'rite is the entire file. Examples: W - Write entire file *W - Write current line Wabc - Write entire file to 'abc' =Wabc - Write tagged lines to 'abc' X [filename] - Write file and eXit This command behaves exactly as the 'W'rite command, followed immediatly by a 'Q'uit command. It provides a shorthand way of saving your file and leaving the editor. Examples: X - Write file & exit Xabc - Write to 'abc' and exit ?<text> - Search for text The '?' command moves the active line to the first occurance of the specified string within the active range. The default range assumed for '?' is one character past the current cursor position (in visual mode) or the first character of the active line (In line by line mode), through to the end of the file. Examples: ?string - Find next occurance of "string" /?string - Find first occurance of "string" $<command> - Execute DOS command The '$' command executes the specified DOS command. Examples: $dir - Execute 'dir' command MICRO-C C-FLEA Compiler Page: 62 <no command> - Goto line If a line range is given without a command, EDT will reposition the "current" line to the beginning of that range. Examples: 100 - Move to line 100 / - Move to start of file 0 - Move to end of file = - Move to tagged line(s) 10.3 Visual mode operation When in VISUAL mode, EDT presents a window on the terminal screen which displays the contents of a section of the file. Editing of the file may be performed directly on the screen via special function keys, and the screen is updated so that you see your changes as they are being performed. Any control characters which exist in the file will be displayed as the corresponding printable character in reverse video. If the end of the file is within the area shown on the screen, the message '*EOF*' is displayed in reverse video. 10.3.1 Entering text Text may be entered into the file being edited, simply by typeing it at the terminal keyboard. EDT automatically places the text in the file, and updates the screen to reflect the new contents. The position of the terminal cursor indicates the position at which the text will be entered. 10.3.2 Positioning the cursor The arrow keys on the terminal may be used to move the cursor around the displayed image. Moving beyond the bottom of the screen causes EDT to scroll forward one line, and shift the screen up. Moving beyond the top of the screen causes EDT to scroll backward one half screen, and redisplay the text. EDT will perform sideways scrolling of the display to allow the cursor to access the entire width of lines which are larger than 80 columns. MICRO-C C-FLEA Compiler Page: 63 10.3.3 Visual mode function keys The following keys on the IBM PC keyboard have special meaning to EDT: Right arrow Moves the cursor forward one character positon in the file, if at the end of a line, the cursor will advance to the first position of the next line. Left arrow Moves the cursor backward one character positon in the file, if at the beginning of a line, the cursor will backup to the last position of the previous line. Up arrow Moves the cursor up one line. If at the top of the screen, the display will scroll backwards by one half a screen page. Down arrow Moves the cursor down one line. If at the bottom of the screen, the display will scroll forward by one line. The cursor may appear to jump back and forth as it is moved up and down, if it ancounters lines which are shorter than the current character position within the line, or lines which contain tabs. This is because whenever possible, the cursor is returned to the same number of physical characters from the start of the line as is was on the first line from which the UP or DOWN arrow was pressed. Page up This key pages backward one screen. (Top line becomes bottom) Page down This key pages forward one screen. (Bottom line becomes top) Home Moves the cursor to the beginning of the line. If it is already at the beginning of a line, it is moved to the beginning of the previous line. End Moves the cursor to the end of the line. If already at the end of a line, it is moved to the end of the next line. MICRO-C C-FLEA Compiler Page: 64 CTRL-PgUp This key moves the cursor to the beginning of the first line in the file. CTRL-PgDn This key moves the cursor to the end of the file. CTRL-Right Arrow Moves the cursor to the beginning of the next word. CTRL-Left Arrow Moves the cursor to the beginning of the previous word. Ins Toggles between character INSERT and OVERWRITE mode. In INSERT mode, all characters typed at the terminal are inserted into the text. In OVERWRITE mode, only the NEWLINE character and data entered at the end of a line is inserted, all other characters will overwrite the existing text. Delete Deletes the character under the cursor, without moving the cursor. Backspace Moves the cursor backward to the previous character, then deletes that character. CTRL-Home Redraws the screen image of the file. This is normally used in the case of the screen being corrupted by data transmission errors, or asynchronus messages from the operating system or its users. F1 Toggles ON/OFF the display of NEWLINE characters at the end of each line of text. F2 Displays the current cursor position, including the actual and character offsets from the start of line. F3 Brings the line the cursor is on to the top of the screen. MICRO-C C-FLEA Compiler Page: 65 F4 Tags one or more lines for a later operation. The tagged lines are displayed in special video if the terminal supports it. Once one line is tagged, pressing this key on another line causes all lines between them to be tagged. Pressing it again on the first line of the tagged range removes the tags. F5 Deletes from the cursor position to the end of the line (inclusive). F6 Deletes from the cursor position to the end of the line (exclusive). F7 Inserts the deleted line text (From Function key 8 or Function key 9) at the current cursor position. F10 or Keypad '+' Prompts for a line mode command, and executes it. See the section on line mode operation. F9 or Keypad '-' Re-executes the last line mode command entered. MICRO-C C-FLEA Compiler Page: 66 +----------------------------------+ | | | ****************************** | | * The MICRO-C/C-FLEA library * | | ****************************** | | | +----------------------------------+ 11. The MICRO-C/C-FLEA Library The library functions described on the following pages are currently available in the MICRO-C library as "standard" functions. ABORT ABORT PROTOTYPE: abort(char *message) ARGUMENTS: message - Pointer to message to display RETURN VALUE: N/A - Function never returns DESCRIPTION: This function writes the string passed as an argument to standard error, and then terminates the program. This provides a simple method of terminating a program on an error condition with a message explaining why. EXAMPLES: abort("Invalid operand\n"); ABS ABS PROTOTYPE: int abs(int number) ARGUMENTS: number - Any integer value RETURN VALUE: The absolute value of "number" DESCRIPTION: The "abs" function returns the absolute value of the argument. If "number" is a positive value, it is returned unchanged. If negative, the negate of that value is returned (giving a positive result). EXAMPLES: difference = abs(value1 - value2); ATOI ATOI PROTOTYPE: int atoi(char *string) ARGUMENTS: string - Pointer to a string containing a decimal number RETURN VALUE: 16 bit integer value DESCRIPTION: The "atoi" function converts an ASCII string containing a signed decimal number (-32768 to 32767) to a 16 bit value which is returned. An unsigned number of the range (0 to 65535) may also be used, and the result if assigned to an "unsigned" variable will be correct. EXAMPLES: value = atoi("1234"); value = atoi("-1"); CHKCH CHKCH PROTOTYPE: int chkch() ARGUMENTS: None RETURN VALUE: 0 - No character available from serial port. !0 - Character read from serial port. DESCRIPTION: The "chkch" function checks to see if a character is ready to be received from the console serial port. If no character is available, a zero (0) is returned, otherwise the character is read and its value is passed back. The CARRIAGE RETURN character (0x0D) will be translated into a NEWLINE (0x0A) for compatibility with 'C'. EXAMPLES: if(chkch() == 0x1B) /* Escape KEY pressed ? */ return; CHKCHR CHKCHR PROTOTYPE: int chkchr() ARGUMENTS: None RETURN VALUE: 0-255 - Character read from serial port. -1 - No character was available. DESCRIPTION: The "chkch" function checks to see if a character is ready to be received from the console serial port. If no character is available, a -1 is returned, otherwise the character is read and its "raw" value is passed back (without translation). EXAMPLES: if(chkchr() == '\r') /* Return KEY pressed ? */ return; CONCAT CONCAT PROTOTYPE: register concat(char *dest, char *source, ...) ARGUMENTS: dest - Pointer to destination string source - Pointer to source string ... - Additional sources may be given RETURN VALUE: None DESCRIPTION: The "concat" function concatinates the given source strings into one destination string. The destination string must be large enough to hold all of the source strings plus the string terminator (zero) byte. No value is returned. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "stdio.h"). EXAMPLES: concat(filename,"/tmp/", input_name); EXIT EXIT PROTOTYPE: exit() ARGUMENTS: None RETURN VALUE: N/A - Function never returns DESCRIPTION: This function terminates the execution of the program, and returns control to the on-board monitor. EXAMPLES: exit(); /* Return to monitor */ FREE FREE PROTOTYPE: free(char *ptr) ARGUMENTS: ptr - Pointer to a previously allocated memory block RETURN VALUE: None DESCRIPTION: The "free" function releases (de-allocates) a block of memory that was obtained via a call to "malloc", and returns it to the heap. This makes it available for use by other memory allocations. EXAMPLES: if(!(ptr = malloc(BUFSIZ))) /* Allocate a temporary buffer */ abort("Not enough memory"); /* ... Use the memory block ... */ free(ptr); /* Release temporary buffer */ GETCH GETCH PROTOTYPE: int getch() ARGUMENTS: None RETURN VALUE: Value of a character read from the serial port. DESCRIPTION: This function reads a single character from the console serial port, and returns it as a positive value in the range of 0 to 255. If the character is a carriage return (0x0D), is translated into a NEWLINE (0x0A) for compatibility with 'C'. EXAMPLES: while(getch() != 0x1B); /* Wait for an ESCAPE character */ GETCHR GETCHR PROTOTYPE: int getchr() ARGUMENTS: None RETURN VALUE: Value of a character read from the serial port. DESCRIPTION: This function reads a single character from the console serial port, and returns it as a positive value in the range of 0 to 255. The character is read in "raw" format, with no translations performed. EXAMPLES: while(getchr() != '\r'); /* Wait for a RETURN */ GETSTR GETSTR PROTOTYPE: char *getstr(char *buffer, int size) ARGUMENTS: buffer - Pointer to string to receive line size - Maximum size of line to read RETURN VALUE: The number of characters received into the line. DESCRIPTION: The "getstr" function reads a string of character from the serial port and places them into the specified character buffer until either a NEWLINE character is encountered, or the limit of "size" character is read. The string is terminated with the standard NULL (00) character. The trailing NEWLINE '\n' character is NOT included in the output buffer. The BACKSPACE or DEL keys can be used to edit the input line. EXAMPLES: getstr(input_line, 80); INPx INPx PROTOTYPE: int inp1(); int inp2(); int inp3(); int inp4(); ARGUMENTS: None RETURN VALUE: 8 bit value (0-255) read from the input port. DESCRIPTION: These functions read an 8 bit value from a parallel I/O port. EXAMPLES: if(inp1() & 0x01) outp2(inp2() | 0x01); ISALNUM ISALNUM PROTOTYPE: int isalnum(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is alphabetic or numeric 0 if 'c' is not alphabetic or numeric DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter in either upper or lower case or if 'c' is a numeric digit, otherwise FALSE (0) is returned. EXAMPLES: while(isalnum(*ptr)) /* Copy over symbol name */ *name++ = *ptr++; ISALPHA ISALPHA PROTOTYPE: int isalpha(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is alphabetic 0 if 'c' is not alphabetic DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter in either upper or lower case, otherwise FALSE (0) is returned. EXAMPLES: flag = isalpha(input_char); ISASCII ISASCII PROTOTYPE: int isascii(int c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is an ASCII character 0 if 'c' is not an ASCII character DESCRIPTION: Returns TRUE (1) if the passed character 'c' is a valid ASCII character (0x00-0xFF), otherwise FALSE (0) is returned. EXAMPLES: if(!isascii(*ptr)) abort("Invalid character data"); ISCNTRL ISCNTRL PROTOTYPE: int iscntrl(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a "control" character 0 if 'c' is not a "control" character DESCRIPTION: Returns TRUE (1) is the passed character 'c' is an ASCII "control" character (0x00-0x1F or 0x7F), otherwise FALSE (0) is returned. EXAMPLES: putch(iscntrl(c) ? '.' : c); /* Display controls as '.' */ ISDIGIT ISDIGIT PROTOTYPE: int isdigit(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is numeric 0 if 'c' is not numeric DESCRIPTION: Returns TRUE (1) is the passed character 'c' is an ASCII digit ('0'-'9'), otherwise FALSE (0) is returned. EXAMPLES: value = 0; while(isdigit(*ptr)) value = (value * 10) + (*ptr++ - '0'); ISGRAPH ISGRAPH PROTOTYPE: int isgraph(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a non-space printable character 0 if 'c' is a space or not printable DESCRIPTION: Returns TRUE (1) if the passed character 'c' is a printable ASCII character other than a space character, otherwise FALSE (0) is returned. EXAMPLES: putch(isgraph(c) ? c : '.'); ISLOWER ISLOWER PROTOTYPE: int islower(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is lower case alphabetic 0 if 'c' is not lower case alphabetic DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter of lower case, otherwise FALSE (0) is returned. EXAMPLES: flag = islower(input_char); ISPRINT ISPRINT PROTOTYPE: int isprint(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a printable character 0 if 'c' is not printable DESCRIPTION: Returns TRUE (1) if the passed character 'c' is a printable ASCII character, otherwise FALSE (0) is returned. EXAMPLES: while(isprint(*ptr)) ++ptr; ISPUNCT ISPUNCT PROTOTYPE: int ispunct(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a printable non-alphanumeric character 0 if 'c' is not printable or alphanumeric DESCRIPTION: Returns TRUE (1) if the passed character 'c' is a printable ASCII character which is not a letter of the alphabet or a numeric digit, otherwise FALSE (0) is returned. EXAMPLES: while(ispunct(*ptr)) ++ptr; ISSPACE ISSPACE PROTOTYPE: int isspace(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a space character (space, tab or newline) 0 if 'c' is not a space character DESCRIPTION: Returns TRUE (1) if the passed character 'c' is one of a space, tab or newline, otherwise FALSE (0) is returned. EXAMPLES: while(isspace(*ptr)) ++ptr; ISUPPER ISUPPER PROTOTYPE: int isupper(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is upper case alphabetic 0 if 'c' is not upper case alphabetic DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter of upper case, otherwise FALSE (0) is returned. EXAMPLES: flag = isupper(input_char); ISXDIGIT ISXDIGIT PROTOTYPE: int isxdigit(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a hexidecimal digit 0 if 'c' is not a hexidecimal digit DESCRIPTION: Returns TRUE (1) is the passed character 'c' is an valid ASCII hexidecimal digit ('0'-'9', 'A'-'F', 'a'-'f'), otherwise FALSE (0) is returned. EXAMPLES: value = 0; while(isxdigit(*ptr)) value = (value * 16) + (isdigit(*ptr) ? *ptr++ - '0' : toupper(*ptr++) - ('A'-10)); LONGJMP LONGJMP PROTOTYPE: longjmp(int savenv[2], int rvalue) ARGUMENTS: savenv - Save area for program context rvalue - Value to be returned by "setjmp" RETURN VALUE: N/A - Function never returns DESCRIPTION: The "longjmp" function causes execution to transfer to the "setjmp" call which set up the "savenv" variable. The "setjmp" function will appear to return the value of "rvalue". NOTE-1: "longjmp" may only be used from within the function calling "setjmp" or a function which has been called "beneath" that function. IT MUST NOT BE USED AFTER THE FUNCTION CALLING "SETJMP" HAS TERMINATED. NOTE-2: If "rvalue" is zero, the function calling "setjmp" will assume that it is returning from initialization. Unless you want this unusual behavior, you should not pass a return value of zero to "longjmp". See also SETJMP. EXAMPLES: if(getch() == ('C'-'@')) /* If Control-C entered... */ longjmp(savearea, 1); /* Return to main function */ LONGMATH LONGMATH PROTOTYPES: int longadd(char *num1, char *num2); int longsub(char *num1, char *num2); longmul(char *num1, char *num2); longdiv(char *num1, char *num2); int longshr(char *num1); int longshl(char *num1); longcpy(char *num1, char *num2); longset(char *num1, unsigned value); int longtst(char *num1); int longcmp(char *num1, char *num2); extern char Longreg[]; ARGUMENTS: num1 - First LONG operand, receives result if generated num2 - Second LONG operand, is not altered value - 16 bit value to initialize LONG number RETURN VALUE: longadd - 0 = Ok, 1 = addition overflowed longsub - 0 = Ok, 1 = subtraction underflowed longshr - Carry out of shift (1/0) longshl - Carry out of shift (1/0) longtst - 0 = Number is zero, !0 = Number is not zero longcmp - 0 = (num1 == num2), 1 = (num1 > num2), -1 = (num1 < num2) DESCRIPTION: This set of functions performs basic arithmetic functions on LONG numbers: longadd(num1, num2) -> num1 += num2 longsub(num1, num2) -> num1 -= num2 longmul(num1, num2) -> num1 *= num2 , Longreg = num1 * num2 longdiv(num1, num2) -> num1 /= num2 , Longreg = num1 % num2 longshr(num1) -> num1 >>= 1 longshl(num1) -> num1 <<= 1 longcpy(num1, num2) -> num1 = num2 longset(num1, value) -> num1 = (long) value longtst(num1) -> Test (num1 != 0) longcmp(num1, num2) -> Compare num1 and num2 As shipped, a LONG number is 32 bits (4 bytes) in size, however this can be changed by altering the LONGMATH.ASM in the library. For a complete example of using these functions, refer to the LONGCALC.C example program included with the package. MALLOC MALLOC PROTOTYPE: char *malloc(int size) ARGUMENTS: size - Size of memory block to allocate (in bytes). RETURN VALUE: 0 - Memory allocation failed !0 - Pointer to allocated memory block DESCRIPTION: The "malloc" function allocates a block of memory of the specified size from the heap, and returns a pointer to it. This memory will remain allocated until it is explicitly released with the "free" function. EXAMPLES: if(!(ptr = malloc(BUFSIZ))) /* Allocate a temporary buffer */ abort("Not enough memory"); /* ... Use the memory block ... */ free(ptr); /* Release temporary buffer */ MAX MAX PROTOTYPE: int max(int value1, int value2) ARGUMENTS: value1 - Any integer value value2 - Any integer value RETURN VALUE: The greater of "value1" or "value2" DESCRIPTION: The "max" function returns the higher of its two argument values. EXAMPLES: biggest = max(a, b); MEMCPY MEMCPY PROTOTYPE: memcpy(char *dest, char *source, unsigned size) ARGUMENTS: dest - Pointer to the destination source - Pointer to the souce size - Number of bytes to copy RETURN VALUE: None DESCRIPTION: The "memcpy" function will copy the specified number of bytes from the source to the destination. EXAMPLES: memcpy(buffer1, buffer2, 256); MEMSET MEMSET PROTOTYPE: memset(char *block, char value, unsigned size) ARGUMENTS: block - Pointer to a block of memory value - Value to initialize memory with size - Number of bytes to initialize RETURN VALUE: None DESCRIPTION: Sets a block of memory beginning at the pointer "block", for "size" bytes to the byte value "value". EXAMPLES: memset(buffer, 0, 100); MIN MIN PROTOTYPE: int min(int value1, int value2) ARGUMENTS: value1 - Any integer value value2 - Any integer value RETURN VALUE: The smaller of "value1" or "value2" DESCRIPTION: The "min" function returns the lower of its two argument values. EXAMPLES: least = min(a, b); NARGS NARGS PROTOTYPE: int nargs() ARGUMENTS: None RETURN VALUE: The number of arguments passed to the calling function DESCRIPTION: Returns the number of arguments passed to a "register" function. NOTE: When calling a "register" function, MICRO-C loads the accumulator with the number of arguments just prior to calling the function. This "nargs" routine is simply a null definition which returns with the same value in the accumulator as was there when it was called. Therefore "nargs" MUST BE THE FIRST ARITHMETIC ENTITY EVALUATED WITHIN THE REGISTER FUNCTION or the contents of the accumulator will be lost. Some examples of "register" definitions and the use of "nargs" may be found in the library source code. EXAMPLES: first_arg = nargs() * 2 + &arguments; OUTPx OUTPx PROTOTYPE: outp1(char value); outp2(char value); outp3(char value); outp4(char value); ARGUMENTS: value - 8 bit value to be written to port. RETURN VALUE: None DESCRIPTION: These functions write an 8 bit value to a parallel I/O port. EXAMPLES: if(inp1() & 0x01) outp2(inp2() | 0x01); PEEK PEEK PROTOTYPE: int peek(unsigned address) ARGUMENTS: address - 16 bit memory address RETURN VALUE: The 8 bit value read from the given memory address DESCRIPTION: The "peek" function reads and returns a byte (8 bits) from memory as an integer value between 0 and 255. EXAMPLES: while(peek(0)); /* Wait for flag to clear */ PEEKW PEEKW PROTOTYPE: int peekw(unsigned address) ARGUMENTS: address - 16 bit memory address RETURN VALUE: The 16 bit value read from the given memory address DESCRIPTION: The "peekw" function reads and returns a word (16 bits) from memory as an integer value between 0 and 65535 (-1). EXAMPLES: var = peekw(0)); POKE POKE PROTOTYPE: poke(unsigned address, char value) ARGUMENTS: address - 16 bit memory address value - Value to be written to memory RETURN VALUE: None DESCRIPTION: The "poke" function writes a byte (8 bit) value to memory. EXAMPLES: poke(0, 0); /* Write 0 to location 0 */ POKEW POKEW PROTOTYPE: pokew(unsigned address, int value) ARGUMENTS: address - 16 bit memory address value - Value to be written to memory RETURN VALUE: None DESCRIPTION: The "pokew" function writes a word (16 bit) value to memory. EXAMPLES: pokew(0, 0); /* Write 0 to locations 0 and 1 */ PRINTF PRINTF PROTOTYPE: register printf(char *format, arg, ...) ARGUMENTS: format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: The "printf" function performs a formatted print to console serial port. The 'format' string is written to the serial port with the arguments substituted for special "conversion characters". These "conversion characters" are identified by a preceeding '%', and may be one of the following: b - Binary number c - Character d - Decimal (signed) number o - Octal number s - String u - Unsigned decimal number x - Hexidecimal number % - A single percent sign (No argument used) A numeric "field width" specifier may be placed in between the '%' and the conversion character, in which case the value will be output in a field of that width. If the "field width" is a negative number, the output will be left justified in the field, otherwise it is right justified. If the field width contains a leading '0', then the output field will be padded with zero's, otherwise spaces are used. If no "field width" is given, the output is free format, using only as much space as required. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "stdio.h"). EXAMPLES: printf("Hello world!!!\n"); printf("%u interrupts have occured!\n", int_count); PUTCH PUTCH PROTOTYPE: putch(char c) ARGUMENTS: c - Any character value RETURN VALUE: None DECRIPTION: This function writes the character 'c' to the console serial port. The NEWLINE character is translated into a LINE-FEED, followed by a CARRIAGE return, which causes the printing position to advance to the first column of the next line. EXAMPLES: putch('*'); putch('\n'); PUTCHR PUTCHR PROTOTYPE: putchr(char c) ARGUMENTS: c - Any character value RETURN VALUE: None DECRIPTION: This function writes the character 'c' to the console serial port. The character is written in "raw" format, with no translations of any kind. EXAMPLES: putchr('*'); putchr('\r'); PUTSTR PUTSTR PROTOTYPE: putstr(char *string) ARGUMENTS: string - Pointer to a character string RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The "putstr" function writes the specified string to the serial port. The zero terminating the string is NOT written. EXAMPLES: putstr("Text message"); RAND RAND PROTOTYPE: unsigned rand(unsigned limit) ARGUMENTS: limit - Maximum value to return RETURN VALUE: A pseudo-random number in the range of 0 to (limit-1) DESCRIPTION: The "rand" function calculates the next value of a pseudo-random sequence, based on a 16 bit unsigned "seed" value, which it maintains in the global variable "RANDSEED". The new value is stored as the new seed value, and is then divided by the "limit" parameter, to obtain the remainder, which is returned. This results in a random number in the range of zero (0) to (limit - 1). Any particular sequence may be repeated, by reseting the "RANDSEED" value. EXAMPLES: value = rand(52); SETJMP SETJMP PROTOTYPE: int setjmp(int savenv[2]) ARGUMENTS: savenv - Save area for program context RETURN VALUE: 0 is returned when actually called Value passed to "longjmp" is returned otherwise DESCRIPTION: When called, the "setjmp" function stores the current execution state of the program into the passed integer array, and returns the value zero. The "longjmp" function may then be used to return the program to the "setjmp" call. In this case, the value returned by "setjmp" will be the value which was passed to "longjmp". This allows the function containing "setjmp" to determine which call to "longjmp" transfered execution to it. See also LONGJMP. EXAMPLES: switch(setjmp(savearea)) { case 0 : printf("Longjmp has been set up"); break; case 1 : printf("Control-C Interrupt"); break; case 2 : printf("Reset command executed"); break; default: printf("Software error trap"); break; } SPRINTF SPRINTF PROTOTYPE: register sprintf(char *dest, char *format, arg, ...) ARGUMENTS: dest - Pointer to destination string format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: The "sprintf" routine performs a formatted print to a string in memory. The "format" string is written to the destination string with the arguments substituted for special "conversion characters". See "printf" for more information on format strings. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "stdio.h"). EXAMPLES: sprintf(header_file, "/lib/%s.h", header_name); SQRT SQRT PROTOTYPE: int sqrt(unsigned value) ARGUMENTS: value - Number for which to calculate square root RETURN VALUE: The integer square root (rounded up) of the argument value DESCRIPTION: The SQRT function returns the smallest number which when multiplied by itself will give a number equal to or larger that the argument value. EXAMPLES: /* * Draw a circle about point (x, y) of radus (r) */ circle(x, y, r) int x, y, r; { int i, j, k, rs, lj; rs = (lj = r)*r; for(i=0; i <= r; ++i) { j = k = sqrt(rs - (i*i)); do { plot_xy(x+i, y+j); plot_xy(x+i, y-j); plot_xy(x-i, y+j); plot_xy(x-i, y-j); } while(++j < lj); lj = k; } } STRCAT STRCAT PROTOTYPE: char *strcat(char *dest, char *source) ARGUMENTS: dest - Pointer to destination string source - Pointer to source string RETURN VALUE: Pointer to zero terminating destination string DESCRIPTION: This function concatinates the source string onto the tail of the destination string. The destination string must be large enough to hold the entire contents of both strings. EXAMPLES: strcat(program_name, ".c"); STRCHR STRCHR PROTOTYPE: char *strchr(char *string, char chr) ARGUMENTS: string - Pointer to a character string chr - Character to look for RETURN VALUE: Pointer to the first occurance of 'chr' in 'string' Zero (0) if character was not found DECRIPTION: Searches the passed string got the first occurance of the specified character. If the character is found, a pointer to its position in the string is returned. If the character is not found, a null pointer is returned. The null (0) character is treated as valid data by this function, thus: strchr(string, 0); would return the position of the null terminator of the string. EXAMPLES: comma = strchr(buffer, ','); STRCMP STRCMP PROTOTYPE: int strcmp(char *string1, char *string2) ARGUMENTS: string1 - Pointer to first string string2 - Pointer to second string RETURN VALUE: 0 - Strings match exactly 1 - String1 is greater than string2 -1 - String2 is greater than string1 DESCRIPTION: This function compares two strings character by character. If the two strings are identical, a zero (0) is returned. If the first string is greater than the second (as far as ASCII is concerned), a one (1) is returned. If the second string is greater, a negative one (-1) is returned. EXAMPLES: if(!strcmp(command, "quit")) exit(0); STRCPY STRCPY PROTOTYPE: char *strcpy(char *dest, char *source) ARGUMENTS: dest - Pointer to destination string souce - Pointer to source string RETURN VALUE: Pointer to zero terminating destination string DESCRIPTION: This function copies the source string to the destination string. All data is copied up to and including the zero byte which terminates the string. The destination string must be large enough to hold the entire source. EXAMPLES: strcpy(filename, argv[1]); STRLEN STRLEN PROTOTYPE: int strlen(char *string) ARGUMENTS: string - Pointer to a character string RETURN VALUE: The length of the string DECRIPTION: Returns the length in character of the passed string. The length does not include the zero byte which terminates the string. EXAMPLES: length = strlen(command); TOLOWER TOLOWER PROTOTYPE: char tolower(char c) ARGUMENTS: c - Any character value RETURN VALUE: The value of 'c', converted to lower case DESCRIPTION: Returns the value of 'c' converted to lower case. If 'c' is not a letter of upper case, no change is made, and the original value of 'c' is returned. EXAMPLES: input_char = tolower(getch()); TOUPPER TOUPPER PROTOTYPE: char toupper(char c) ARGUMENTS: c - Any character value RETURN VALUE: The value of 'c', converted to upper case DESCRIPTION: Returns the value of 'c' converted to upper case. If 'c' is not a letter of lower case, no change is made, and the original value of 'c' is returned. EXAMPLES: putch(toupper(output_char)); MICRO-C C-FLEA Compiler TABLE OF CONTENTS Page 1. INTRODUCTION 1 1.1 Memory configuration 1 1.2 Code Portability 1 1.3 The compiling process 2 2. THE COMMAND CO-ORDINATOR 3 2.1 The CCF command 3 3. THE MICRO-C PROGRAMMING LANGUAGE 5 3.1 Constants 5 3.2 Symbols 5 3.3 Arrays & Pointers 9 3.4 Functions 9 3.5 Structures & Unions 10 3.6 Control Statements 13 3.7 Expression Operators 15 3.8 Inline Assembly Language 17 3.9 Preprocessor Commands 18 3.10 Error Messages 19 3.11 Quirks 24 4. ADVANCED TOPICS 28 4.1 Conversion Rules 28 4.2 Assembly Language Interface 29 4.3 Compiling for ROM 31 5. THE MICRO-C COMPILER 32 5.1 The MCCCF command 32 6. THE MICRO-C PREPROCESSOR 33 6.1 The MCP command 34 6.2 Preprocesor Commands 35 6.3 Error messages 38 7. THE MICRO-C OPTIMIZER 40 7.1 The MCOCF command 40 8. THE SOURCE LINKER 41 8.1 The SLINK Command 41 MICRO-C C-FLEA Compiler Table of Contents Page 8.2 Multiple Input Files 42 8.3 The External Index File 43 8.4 Source file information 45 8.5 The SCONVERT command 46 8.6 The SRENUM command 47 8.7 The SINDEX command 48 8.8 The SLIB command 48 8.9 Making a source library 50 9. THE MAKE UTILITY 51 9.1 MAKEfiles 51 9.2 Directives 54 9.3 The MAKE command 55 9.4 The TOUCH command 56 10. EDT - Text editor 57 10.1 Introduction 57 10.2 Line mode operation 57 10.3 Visual mode operation 62 11. The MICRO-C/C-FLEA Library 66