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Text File | 1990-02-12 | 28.6 KB | 1,493 lines

;*** AS V1.00 PROGRAM: ONE-PASS ASSEMBLER - BY ├RAIG ┬RUCE - 15-╧CT-1994 ; ╘HIS IS THE ┬UDDY-ASSEMBLER VERSION OF THE PROGRAM ;TODO: -IMPLEMENT STORAGE CLASSES: $00=INTERNAL, $01=REL.LABEL, $80=EXPORTED ; -IMPLEMENT ALL VAR TYPES: 0=VALUE, 1=ADDRESS, 2=ADDR.HIGH, 3=ADDR.LOW ; -IMPLEMENT SOURCE COLUMN, MAKE LINE:COL POINT TO START OF CUR TOKEN ; -MAKE IT SO YOU CAN USE A "\<├╥>" TO CONTINUE A LINE ; -ADD MORE OPERATORS: * / & ▄ ▐ FULL PRECEDENCE? ; -CACHE CURRENT SYMBOL ; -SUBTLE PROBLEM: SHORT BLOCKS ON READ WILL CAUSE TOKENS TO BE SPLIT ; BECAUSE OF BUFFER FILLING WITH SPACES. SOLUTION: PUSH SHORT BLOCKS ; TO HIGH END OF BUFFER, SET POINTER? BETTER SOLUTION: READ UNTIL ; BUFFER IS FULL OR EOF IS HIT. .SEQ ACEHEAD.S .ORG ACE┴PP┴DDRESS .OBJ "@0:AS" JMP MAIN .BYTE ACE╔─1,ACE╔─2,ACE╔─3 .BYTE 64,0 ;** STACK,RESERVED ;======== GLOBAL DECLARATIONS ======== SOURCE╞CB = 2 ;(1) ;FILE CONTROL BLOCK OF CURRENT INPUT FILE BUFPTR = 3 ;(1) ;BYTE OFFSET INSIDE OF SOURCE BUFFER SOURCE╠INE = 4 ;(4) ;SOURCE FILE CURRENT LINE NUMBER = 8 ;(4) ;TOKEN: 32-BIT NUMBER VALUE STRING╠EN = 12 ;(1) ;LENGTH OF STRING IN STRING BUFFER PREV├HAR = 13 ;(1) ;PREVIOUS CHARACTER SCANNED, NEXT READ (1-TOO-FAR) TOKEN╘YPE = 14 ;(1) ;TOKEN: TYPE TOKEN╬EXT├HAR = 15 ;(1) ;TOKEN: NEXT CHAR AFTER TOKEN TOKEN╬UM┬YTES = 16 ;(1) ;TOKEN: NUMBER LENGTH (1-4 BYTES) TOKEN├HAR = 17 ;(1) ;TOKEN: CHARACTER NAME = 18 ;(2) ;POINTER TO SOURCE FILENAME SOURCE├OL = 20 ;(1) ;SOURCE FILE COLUMN WITHIN LINE NEXT╨LUS╠AB = 22 ;(4) ;NUMBER FOR NEXT "+" LABEL PREV═INUS╠AB = 26 ;(4) ;NUMBER FOR PREVIOUS "-" LABEL ADDRESS = 30 ;(4) ;CURRENT MEMORY ADDRESS FOR CODE ASSEMBLY HASH╓AL = 34 ;(2) ;16-BIT HASH VALUE RESULT HASH╨TR = 36 ;(2) ;POINTER TO SELECTED ENTRY IN IDENTIFIER HASH TABLE ID╨TR = 38 ;(4) ;POINTER TO CURRENT IDENTIFIER DESCRIPTOR ID╓AL = 42 ;(4) ;VALUE OF CURRENT IDENTIFIER VAR╨TR = 46 ;(4) ;POINTER TO CURRENT IDENTIFIER TO BE DEFINED FILE╨TR = 50 ;(4) ;POINTER TO CURRENT FILE INFO DESCRIPTOR ID╘YPE = 54 ;(1) ;TYPE OF CURRENT IDENTIFIER (VALUE,ADDRESS,UNRES) ORIGIN╙ET = 55 ;(1) ;FLAG INDICATING WHETHER ORIGIN HAS BEEN SET EXP╨LUS├OUNT = 56 ;(1) ;NUMBER OF PLUS MONADIC OPERATORS OF AN OPERAND EXP═INUS├OUNT = 57 ;(1) ;NUMBER OF MINUS MONADIC OPERATORS OF AN OPERAND EXP╠ESS├OUNT = 58 ;(1) ;NUMBER OF LOW-BYTE MONADIC OPERATORS OF AN OPERAND EXP╟REATER├OUNT = 59 ;(1) ;NUMBER OF HIGH-BYTE MONADIC OPERATORS OF AN OPERAND EXP╧FFSET = 60 ;(1) ;OFFSET OF CUR OPERAND IN AN EXPRESSION DESCRIPTOR EXP╨TR = 62 ;(4) ;POINTER TO EXPRESSION DESCRIPTOR IN FAR MEMORY ADDRESS╧RIGIN = 66 ;(4) ;ORIGIN AS SET BY ORG DIRECTIVE HOLE├OUNT = 70 ;(4) ;NUMBER OF HOLES (UNRESOLVED REFERENCES) REL╚OLE├OUNT = 74 ;(4) ;NUMBER OF HOLES FOR RELATIVE (INTERNAL) REFERENCES INSTR╬UM = 78 ;(1) ;ASSEM INSTR: INSTRUCTION NUMBER (1-56) INSTR┴DDR═ODE = 79 ;(1) ;ASSEM INSTR: ADDRESSING MODE FOR INSTR (1-12) INSTR╓ALUE = 80 ;(2) ;ASSEM INSTR: OPERAND VALUE FOR INSTR (8/16 BIT) INSTR╓ALUE╘YPE = 82 ;(1) ;ASSEM INSTR: OPERAND VALUE TYPE INSTR╧PCODE = 83 ;(1) ;ASSEM INSTR: OPCODE OF INSTR/ADDRMODE INSTR╠EN = 84 ;(1) ;ASSEM INSTR: LENGTH OF INSTRUCTION MEM┬UF╨AGE = 85 ;(1) ;MEM PUT: PAGE OF BUFFER MEM┬UF╨TR = 86 ;(4) ;MEM PUT: POINTER TO 1╦ MEMORY-BUFFER BLOCK MEM╨UT╓ALS = 90 ;(4) ;MEM PUT: VALUES TO PUT INTO MEMORY MEM╨UT├OUNT = 94 ;(1) ;MEM PUT: NUMBER OF VALUES TO PUT INTO MEMORY MEM╨UT╨AGE = 95 ;(1) ;MEM PUT: CURRENT PAGE FOR VALUES NEW╠INE = 96 ;(4) ;CURRENT INPUT LINE NEW├OL = 100 ;(1) ;CURRENT INPUT COLUMN ARG = 102 ;(2) ;CURRENT COMMAND LINE ARGUMENT RESERVED = 104 MEM╫ORK = 112 ;(16) ;WORK AREA FOR THE MEMORY ROUTINES/LOW-LEVEL WORK STR─ELIMIT = 112 ;(1) ;STRING TOKENIZE: DELIMITER--OVERLAP NUM┬ASE = 113 ;(1) ;NUMBER TOKENIZE: BASE--OVERLAP NUM╙AVE = 114 ;(4) ;NUMBER TOKENIZE: SAVE--OVERLAP WORK = 112 ;(16) ;MISCELLANEOUS WORK--LOW-LEVEL--OVERLAP HASH╘ABLE╨AGES = 16 HASH╘ABLE┼NTRIES╚IGH = 4 HASH╘ABLE═ASK = $03 SYM╬EW = $81 SYM╒NRESOLVED = $80 SYM╞OUND = 0 TOKEN╔DENTIFIER = 0 TOKEN╬UMBER = 1 TOKEN╙TRING = 2 TOKEN╙PECIAL = 3 TOKEN┼╧╞ = 4 CHR├╥ = $0D CHR╤UOTE = $22 CHR╘AB = $09 CHR┼╧╞ = $00 ERR╧K = 0 ;OK ERR╔DENT╘OO╠ONG = 1 ;AN IDENTIFIER TOKEN EXCEEDS 240 CHARS IN LENGTH ERR╙TRING╘OO╠ONG = 2 ;A STRING LITERAL EXCEEDS 255 CHARS IN LENGTH ERR╬O├LOSE╤UOTE = 3 ;RAN INTO A ├╥ BEFORE END OF STRING LITERAL ERR┬AD╬UMBER = 4 ;INVALID NUMERIC LITERAL ERR╬UM╧VERFLOW = 5 ;NUMERIC LITERAL VALUE OVERFLOWS 32-BITS ERR╙YNTAX = 6 ;SYNTAX ERROR ERR╔NVAL╙TR╧PERS = 7 ;ATTEMPT TO PERFORM NUMERIC OPERATORS ON A STRING ERR╘OO═ANY╧PERANDS = 8 ;EXPRESSION HAS MORE THAN 17 OPERANDS ERR╔NSUFFICIENT═EMORY = 9 ;RAN OUT OF MEMORY DURING COMPILATION PROCESS ERR╥EDEFINED╙YMBOL = 10 ;ATTEMPT TO REDEFINE A SYMBOL ERR╧RIGIN╬OT╙ET = 11 ;ATTEMPT TO ASSEMBLE CODE WITH CODE ORIGIN NOT SET ERR╔NTERN┴SSIGN = 12 ;INTERNAL ERROR: ATTEMPT TO ASSIGN TO UNEXPECTED ID ERR╬ON╬UM╔D┼XPR = 13 ;NON-NUMERIC SYMBOL IN A NUMERIC EXPRESSION ERR┼XPECT╧PERATOR = 14 ;EXPECTING AN OPERATOR ERR┼XPECT╧PERAND = 15 ;EXPECTING AN OPERAND ERR┼XPECT├OMMAND = 16 ;EXPECTING A COMMAND ERR╓ALUE╘OO╠ARGE = 17 ;VALUE IS TOO LARGE FOR OPERATION (OR IS NEGATIVE) ERR┬RANCH╘OO╞AR = 18 ;BRANCH OUT OF RANGE ERR╬OT╔MPLEMENTED = 19 ;FEATURE IS NOT (YET) IMPLEMENTED ERR╫RONG┴DMODE = 20 ;INSTRUCTION DOES NOT SUPPORT GIVEN ADDRESS MODE ERR┴DDRESS╫RAP = 21 ;ADDRESS WRAPED AROUND 64╦ CODE ADDRESS SPACE ERR╧BJECT╞ILE = 22 ;ERROR TRYING TO WRITE OUTPUT OBJECT FILE ERR╬OT╥ESOLVED┼XPR = 23 ;DIRECTIVE REQUIRES RESOLVED EXPRESSION ERR╧RIGIN┴LREADY╙ET = 24 ;CODE ORIGIN ALREADY SET; YOU CAN'T SET IT TWICE ERR╒NRESD╥EFERENCES = 25 ;UNRESOLVED REFERENCE ERR─OT├OMMAND = 26 ;THIS ASSEMBLER DOESN'T ACCEPT DOT COMMANDS DEBUG .BUF 1 ;DISPLAY DEBUG INFORMATION: $FF=YES, $00=NO SYM─UMP .BUF 1 ;DISPLAY SYMBOL TABLE DUMP: $FF=YES, $00=NO OUTPUT╘YPE .BUF 1 ;TYPE OF OUTPUT MODULE: $00=BINARY, $01=RELOC, $80=LINK ;======== MAIN ROUTINE ======== MAIN = * ;** CHECK FOR LARGE ENOUGH ╘╨┴ SEC LDA #<BSS┼ND CMP ACE═EM╘OP+0 LDA #>BSS┼ND SBC ACE═EM╘OP+1 BCS + JMP MAIN├ONT + LDA #<TPA═SG LDY #>TPA═SG JSR EPUTS DIE = * LDA #1 LDX #0 JMP EXIT TPA═SG = * .ASC "AS: ╔NSUFFICIENT PROGRAM SPACE TO RUN IN" .BYTE CHR├╥,0 USAGE = * LDA #<USAGE═SG LDY #>USAGE═SG JSR EPUTS JMP DIE USAGE═SG = * .ASC "USAGE: AS [-HELP] [-S] [-D] [FILE ...]" .BYTE CHR├╥,CHR├╥ .ASC " -HELP : PRODUCE THIS INFORMATION, DON'T RUN" .BYTE CHR├╥ .ASC " -S : PRODUCE SYMBOL TABLE DUMP AT END" .BYTE CHR├╥ .ASC " -D : PROVIDE DEBUGGING INFORMATION (LOTS)" .BYTE CHR├╥,0 DEFAULT╔NPUT = * .ASC "-STDIN-" .BYTE 0 FILENAME╒SED .BUF 1 MAIN├ONT = * ;** INIT GLOBALS LDA #$00 STA DEBUG ;DEFAULT OFF STA SYM─UMP ;DEFAULT NONE STA OUTPUT╘YPE ;DEFAULT BINARY LDA #$00 STA FILENAME╒SED LDA #0 STA ARG+0 STA ARG+1 JSR AS╔NIT LDX #7 - LDA WRITE─EFAULT╬AME,X STA WRITE╬AME,X DEX BPL - MAIN╬EXT = * JSR CHECK╙TOP INC ARG+0 BNE + INC ARG+1 + LDA ARG+0 LDY ARG+1 JSR GETARG LDA ZP+0 ORA ZP+1 BEQ MAIN┼XIT LDA ZP+0 LDY ZP+1 STA NAME+0 STY NAME+1 LDY #0 LDA (ZP),Y CMP #"-" BNE + JSR HANDLE╞LAGS JMP MAIN╬EXT + JSR ECHO JSR MAIN╞ILE JMP MAIN╬EXT MAIN┼XIT = * BIT FILENAME╒SED BMI + LDA #<DEFAULT╔NPUT LDY #>DEFAULT╔NPUT STA NAME+0 STY NAME+1 JSR ECHO JSR MAIN╙TDIN + LDA #$00 LDX #3 - ORA HOLE├OUNT DEX BPL - CMP #$00 BEQ + JSR FIND╒NRES╙YMBOL LDA #ERR╒NRESD╥EFERENCES JMP ERROR╥EF + JSR WRITE╧BJECT╞ILE JSR DUMP╙YMBOL╘ABLE RTS HANDLE╞LAGS = * INY LDA (ZP),Y BNE + RTS + CMP #"S" BEQ FLAG╙ CMP #"D" BEQ FLAG─ JMP USAGE FLAG╙ = * LDA #$FF STA SYM─UMP JMP HANDLE╞LAGS FLAG─ = * LDA #$FF STA DEBUG JMP HANDLE╞LAGS ECHO = * LDA #<ECHO═SG1 LDY #>ECHO═SG1 JSR EPUTS JSR ECHO╬AME LDA #<ECHO═SG2 LDY #>ECHO═SG2 JMP EPUTS ECHO╬AME = * LDA NAME+0 LDY NAME+1 JMP EPUTS ECHO═SG1 = * .ASC "ASSEMBLING SOURCE FILE " .BYTE CHR╤UOTE,0 ECHO═SG2 = * .BYTE CHR╤UOTE,CHR├╥,0 MAIN╞ILE = * BIT FILENAME╒SED BMI + JSR MAIN┼XTRACT╧BJ + LDA NAME+0 LDY NAME+1 STA ZP+0 STY ZP+1 LDA #"R" JSR OPEN BCC + JSR ECHO╬AME LDA #<MAIN╞ILE┼RR LDY #>MAIN╞ILE┼RR JSR EPUTS JMP DIE + STA SOURCE╞CB JSR AS─RIVER LDA SOURCE╞CB JSR CLOSE LDA #$FF STA FILENAME╒SED RTS MAIN╞ILE┼RR = * .ASC ": ├ANNOT OPEN FILE" .BYTE CHR├╥,0 MAIN╙TDIN = * LDA #STDIN STA SOURCE╞CB JSR AS─RIVER RTS MAIN┼XTRACT╧BJ = * LDX #0 ;COPY-START LDY #0 - LDA (NAME),Y BEQ +++ CMP #":" BEQ + CMP #"/" BNE ++ + TYA TAX INX + INY BNE - + TXA TAY LDX #0 - LDA (NAME),Y STA STRING┬UF,X BEQ + INY INX BNE - + NOP - CPX #3 BCS + RTS + LDA STRING┬UF-2,X CMP #"," BNE + LDA #0 DEX DEX STA STRING┬UF,X JMP - + CMP #"." BEQ + RTS + LDA STRING┬UF-1,X CMP #"S" BEQ + RTS + CPX #18 BCC + LDX #18 + LDA #"," STA STRING┬UF-2,X LDA #"P" STA STRING┬UF-1,X LDA #0 STA STRING┬UF,X - LDA STRING┬UF,X STA WRITE╬AME,X DEX BPL - RTS AS╔NIT = * ;INITIALIZE VARIABLES FOR ASSEMBLY LDX #3 LDA #0 - STA NEW╠INE,X STA NEXT╨LUS╠AB,X STA PREV═INUS╠AB,X STA ADDRESS,X STA HOLE├OUNT,X STA REL╚OLE├OUNT,X DEX BPL - STA NEW├OL LDA #1 STA NEW╠INE+0 STA NEXT╨LUS╠AB+0 LDA #$00 STA ORIGIN╙ET LDA #<$1300 LDY #>$1300 STA ADDRESS+0 STY ADDRESS+1 STA ADDRESS╧RIGIN+0 STY ADDRESS╧RIGIN+1 JSR MALLOC╔NIT JSR INIT╙YMBOL╘ABLE JSR MEM╔NIT RTS ;======== DRIVER ======== AS─RIVER = * LDA #$FF STA BUFPTR LDA #" " STA PREV├HAR - JSR PARSE BCC - RTS WRITE╧B╘RY .BUF 1 WRITE╧B╞D .BUF 1 WRITE╧BJECT╞ILE = * LDA #<WRITE═SG LDY #>WRITE═SG JSR EPUTS LDA #<WRITE╬AME LDY #>WRITE╬AME JSR EPUTS LDA #CHR╤UOTE LDX #STDERR JSR PUTC LDX #STDERR LDA #CHR├╥ JSR PUTC LDA #2 STA WRITE╧B╘RY LDA #<WRITE╬AME LDY #>WRITE╬AME STA ZP+0 STY ZP+1 ;** OPEN OBJECT FOR WRITING - LDA #"W" JSR OPEN BCC ++ LDA ERRNO CMP #ACE┼RR╞ILE┼XISTS BEQ + - LDA #ERR╧BJECT╞ILE JMP ERROR + DEC WRITE╧B╘RY BEQ - JSR REMOVE BCS - JMP -- + STA WRITE╧B╞D ;** WRITE OBJECT DATA LDA ADDRESS╧RIGIN+0 LDX WRITE╧B╞D JSR PUTC LDA ADDRESS╧RIGIN+1 LDX WRITE╧B╞D JSR PUTC LDA WRITE╧B╞D LDX ADDRESS╧RIGIN+0 LDY ADDRESS╧RIGIN+1 JSR MEM╙AVE ;** CLOSE OBJECT LDA WRITE╧B╞D JSR CLOSE BCC + LDA #ERR╧BJECT╞ILE JMP ERROR + LDA #<WRITE╥ANGE═SG1 LDY #>WRITE╥ANGE═SG1 JSR EPUTS LDA ADDRESS╧RIGIN+1 LDX #STDERR JSR FPUTHEX LDA ADDRESS╧RIGIN+0 LDX #STDERR JSR FPUTHEX LDA #<WRITE╥ANGE═SG2 LDY #>WRITE╥ANGE═SG2 JSR EPUTS SEC LDA ADDRESS+0 SBC #1 PHA LDA ADDRESS+1 SBC #0 LDX #STDERR JSR FPUTHEX PLA LDX #STDERR JSR FPUTHEX LDA #<WRITE╥ANGE═SG3 LDY #>WRITE╥ANGE═SG3 JSR EPUTS SEC LDA ADDRESS+0 SBC ADDRESS╧RIGIN+0 STA WORK+0 LDA ADDRESS+1 SBC ADDRESS╧RIGIN+1 STA WORK+1 LDA #0 STA WORK+2 STA WORK+3 LDX #WORK JSR EPUTNUM LDA #<WRITE╥ANGE═SG4 LDY #>WRITE╥ANGE═SG4 JSR EPUTS RTS WRITE─EFAULT╬AME = * .ASC "A.OUT,P" .BYTE 0 WRITE═SG = * .ASC "WRITING OBJECT FILE " .BYTE CHR╤UOTE,0 WRITE╥ANGE═SG1 = * .ASC "CODE RANGE: $" .BYTE 0 WRITE╥ANGE═SG2 = * .ASC "--$" .BYTE 0 WRITE╥ANGE═SG3 = * .ASC " (" .BYTE 0 WRITE╥ANGE═SG4 = * .ASC " BYTES)" .BYTE CHR├╥,0 ;======== PARSER ======== PARSE = * ;** AT BEGINNING OF COMMAND JSR CHECK╙TOP JSR GET╘OKEN LDA TOKEN╘YPE CMP #TOKEN┼╧╞ BNE + SEC RTS + CMP #TOKEN╔DENTIFIER BNE PARSE╬OT╔D LDA TOKEN╬EXT├HAR CMP #"=" BNE + JMP PARSE┼QUATE + CMP #":" BNE + JMP PARSE┴DDRESS + JMP PARSE╔DENTIFIER PARSE╬OT╔D = * CMP #TOKEN╙PECIAL BEQ + SYNTAX┼RROR = * LDA #ERR╙YNTAX JMP ERROR + LDA TOKEN├HAR CMP #CHR├╥ BNE + JMP PARSE┼ND + CMP #"+" BNE + JMP PARSE╨LUS + CMP #"-" BNE + JMP PARSE═INUS + CMP #"#" BNE + JMP PARSE┼ND + CMP #"." BNE + JMP PARSE─OT├OMMAND + JMP SYNTAX┼RROR ;RET: .╪=TOKEN╔DENTIFIER, .┴=NEXT├HAR, .┘=STRLEN, STRING╠EN, STRING┬UF ; .╪=TOKEN╬UMBER, .┘=NUMLEN, NUMBER ; .╪=TOKEN╙TRING, .┴=FIRST├HAR,.┘=STRLEN, STRING╠EN, STRING┬UF ; .╪=TOKEN╙PECIAL, .┴=CHAR PARSE┼QUATE = * JSR PARSE─EFINE╓AR JSR GET╘OKEN CPX #TOKEN╙PECIAL BEQ + - JMP SYNTAX┼RROR + CMP #"=" BNE - LDA #0 JSR PARSE┼XPRESSION CMP #CHR├╥ BNE - JSR EVALUATE┼XPRESSION BCS + JSR ASSIGN╓ARIABLE JMP ++ + JSR ADD╓ARIABLE╚OLE + BIT DEBUG BPL + LDA #<PARSE┼QUATE═SG LDY #>PARSE┼QUATE═SG JSR PUTS + JMP PARSE┼ND PARSE┼QUATE═SG = * .ASC "PARSE┼QUATE: ASSIGN PARSED EXPRESSION TO VARIABLE." .BYTE CHR├╥,0 PARSE┴DDRESS = * JSR PARSE─EFINE╓AR JSR GET╘OKEN CPX #TOKEN╙PECIAL BEQ + - JMP SYNTAX┼RROR + CMP #":" BEQ + JMP SYNTAX┼RROR + JSR PARSE┴SSIGN┴DDRESS BIT DEBUG BPL + LDA #<PARSE┴DDRESS═SG LDY #>PARSE┴DDRESS═SG JSR PUTS + JMP PARSE┼ND PARSE┴DDRESS═SG = * .ASC "PARSE┴DDRESS: ASSIGN CURRENT ADDRESS TO VARIABLE." .BYTE CHR├╥,0 PARSE┴SSIGN┴DDRESS = * BIT ORIGIN╙ET BMI + LDA #ERR╧RIGIN╬OT╙ET JMP ERROR + LDX #3 - LDA ADDRESS,X STA ID╓AL,X DEX BPL - LDA #$01 STA ID╘YPE JMP ASSIGN╓ARIABLE PARSE╨LUS = * LDA #"+" LDY #0 JSR GEN╥EL╠ABEL JSR PARSE─EFINE╓AR JSR PARSE┴SSIGN┴DDRESS BIT DEBUG BPL + LDA #<PARSE╨LUS═SG LDY #>PARSE╨LUS═SG JSR PUTS LDX #NEXT╨LUS╠AB JSR PUTNUM LDA #CHR├╥ JSR PUTCHAR + INC NEXT╨LUS╠AB+0 BNE + INC NEXT╨LUS╠AB+1 BNE + INC NEXT╨LUS╠AB+2 BNE + INC NEXT╨LUS╠AB+3 + JMP PARSE┼ND PARSE╨LUS═SG = * .ASC "PARSE╨LUS: ASSIGN CURRENT ADDRESS TO A SYNTHEIC '+' VARIABLE:" .BYTE 0 PARSE═INUS = * INC PREV═INUS╠AB+0 BNE + INC PREV═INUS╠AB+1 BNE + INC PREV═INUS╠AB+2 BNE + INC PREV═INUS╠AB+3 + LDA #"-" LDY #0 JSR GEN╥EL╠ABEL JSR PARSE─EFINE╓AR JSR PARSE┴SSIGN┴DDRESS BIT DEBUG BPL + LDA #<PARSE═INUS═SG LDY #>PARSE═INUS═SG JSR PUTS LDX #PREV═INUS╠AB JSR PUTNUM LDA #CHR├╥ JSR PUTCHAR + JMP PARSE┼ND PARSE═INUS═SG = * .ASC "PARSE═INUS: ASSIGN CURRENT ADDRESS TO A SYNTHETIC '-' VARIABLE:" .BYTE 0 GEN╥EL╠ABEL = * ;( .┴=TYPE, .┘=RELATIVE ) STA STRING┬UF+1 CMP #"+" BNE + CLC TYA ADC NEXT╨LUS╠AB STA NUMBER+0 LDY #3 LDX #1 - LDA NEXT╨LUS╠AB,X ADC #0 STA NUMBER,X INX DEY BNE - JMP ++ + SEC STY NUMBER+0 LDA PREV═INUS╠AB+0 SBC NUMBER+0 STA NUMBER+0 LDY #3 LDX #1 - LDA PREV═INUS╠AB,X SBC #0 STA NUMBER,X INX DEY BNE - + LDA #"╠" STA STRING┬UF+0 LDA #<STRING┬UF+2 LDY #>STRING┬UF+2 STA ZP+0 STY ZP+1 LDX #NUMBER LDA #1 JSR UTOA INY INY LDA #"C" STA STRING┬UF,Y INY LDA #0 STA STRING┬UF,Y STY STRING╠EN RTS PARSE┼ND = * BIT DEBUG BPL + LDA #<PARSE┼ND═SG LDY #>PARSE┼ND═SG JSR PUTS + CLC RTS PARSE┼ND═SG = * .ASC "-----=-----" .BYTE CHR├╥,CHR├╥,0 PARSE╔DENTIFIER = * ;LINE STARTING WITH AN IDENTIFIER JSR HASH ;** CHECK IF IDENTIFIER IS A PROCESSOR INSTRUCTION LDA STRING╠EN CMP #3 BNE PARSE╔D╬OT╔NSTR LDA HASH╓AL+0 AND #63 TAX LDA INSTR╚ASH╨TRS,X CMP #100 BCS + JSR PARSE╔D├HECK╔NSTR BCS PARSE╔D╬OT╔NSTR JMP INSTR + SEC SBC #100 TAX - LDA INSTR╚ASH╔NDIRECTS,X BEQ PARSE╔D╬OT╔NSTR JSR PARSE╔D├HECK╔NSTR BCS + JMP INSTR + INX BNE - ;** CHECK IF IDENTIFIER IS A DIRECTIVE PARSE╔D╬OT╔NSTR = * JSR CHECK╔F─IRECTIVE BCS PARSE╔D╬OT─IRECTIVE JMP DIRECTIVE ;** CHECK IF IDENTIFIER IS A MACRO PARSE╔D╬OT─IRECTIVE = * LDA #ERR┼XPECT├OMMAND JMP ERROR PARSE─OT├OMMAND = * LDA #ERR─OT├OMMAND JMP ERROR ;======== HANDLE ASSEMBLER DIRECTIVES ======== DIREC╬UM .BUF 1 CHECK╔F─IRECTIVE = * ;( STRING┬UF, STRING╠EN ) : .├╙=NO, .┴=DIR╬UM LDA #0 STA DIREC╬UM DIREC├HECK╬EXT = * LDX DIREC╬UM LDY DIREC╧FFSETS,X LDX #0 - LDA STRING┬UF,X CMP DIREC╬AMES,Y BNE DIREC├HECK├ONT CMP #$00 BNE + LDA DIREC╬UM CLC RTS + INY INX BNE - DIREC├HECK├ONT = * INC DIREC╬UM LDA DIREC╬UM CMP #16 BCC DIREC├HECK╬EXT LDA #0 SEC RTS DIREC╧FFSETS = * .BYTE 00,03,07,10,13,16,20,28,31,37,42,48,54,63,70 DIREC╬AMES = * .ASC "DB" ;DN=01. OFF=00 .BYTE 0 .ASC "BUF" ;DN=02. OFF=03 .BYTE 0 .ASC "DW" ;DN=03. OFF=07 .BYTE 0 .ASC "DT" ;DN=04. OFF=10 .BYTE 0 .ASC "DL" ;DN=05. OFF=13 .BYTE 0 .ASC "ORG" ;DN=06. OFF=16 .BYTE 0 .ASC "INCLUDE" ;DN=07. OFF=20 .BYTE 0 .ASC "IF" ;DN=08. OFF=28 .BYTE 0 .ASC "ELSIF" ;DN=09. OFF=31 .BYTE 0 .ASC "ELSE" ;DN=10. OFF=37 .BYTE 0 .ASC "ENDIF" ;DN=11. OFF=42 .BYTE 0 .ASC "MACRO" ;DN=12. OFF=48 .BYTE 0 .ASC "ENDMACRO" ;DN=13. OFF=54 .BYTE 0 .ASC "EXPORT" ;DN=14. OFF=63 .BYTE 0 .ASC "BSS" ;DN=15. OFF=70 .BYTE 0 DIREC╓ECTORS = * .WORD DIREC─B,DIREC┬UF,DIREC─W,DIREC─T,DIREC─L,DIREC╧RG,DIREC╔NCLUDE .WORD DIREC╔F,DIREC┼LSIF,DIREC┼LSE,DIREC┼NDIF,DIREC═ACRO,DIREC┼NDMACRO .WORD DIREC┼XPORT,DIREC┬SS DIRECTIVE = * ;( .┴=DIR╬UM ) BIT DEBUG BPL + PHA LDA #<DIREC═SG LDY #>DIREC═SG JSR PUTS PLA + ASL TAY LDA DIREC╓ECTORS+0,Y STA WORK+14 LDA DIREC╓ECTORS+1,Y STA WORK+15 JSR + JMP PARSE┼ND + JMP (WORK+14) DIREC═SG = * .ASC "MUST PARSE A DIRECTIVE" .BYTE CHR├╥,0 DIREC╧RG = * BIT ORIGIN╙ET BPL + LDA #ERR╧RIGIN┴LREADY╙ET JMP ERROR + LDA #0 JSR PARSE┼XPRESSION CMP #CHR├╥ BEQ + JMP SYNTAX┼RROR + JSR EVALUATE┼XPRESSION BCC + LDA #ERR╬OT╥ESOLVED┼XPR JMP ERROR + LDA ID╓AL+2 ORA ID╓AL+3 BEQ + LDA #ERR╓ALUE╘OO╠ARGE JMP ERROR + LDA ID╓AL+0 LDY ID╓AL+1 STA ADDRESS+0 STY ADDRESS+1 STA ADDRESS╧RIGIN+0 STY ADDRESS╧RIGIN+1 LDA #$FF STA ORIGIN╙ET BIT DEBUG BPL + LDA #<DIREC╧RG═SG LDY #>DIREC╧RG═SG JSR PUTS LDA ID╓AL+1 JSR PUTHEX LDA ID╓AL+0 JSR PUTHEX LDA #CHR├╥ JSR PUTCHAR + RTS DIREC╧RG═SG = * .ASC "SETTING CODE ORIGIN TO $" .BYTE 0 DIREC─F╙IZE .BUF 1 DIREC─F├HAR .BUF 1 DIREC─B = * LDA #1 BNE DIREC─L╔N DIREC─W = * LDA #2 BNE DIREC─L╔N DIREC─T = * LDA #3 BNE DIREC─L╔N DIREC─L = * LDA #4 DIREC─L╔N = * STA DIREC─F╙IZE BIT ORIGIN╙ET BMI DIREC─F╬EXT LDA #ERR╧RIGIN╬OT╙ET JMP ERROR DIREC─F╬EXT = * LDA #1 JSR PARSE┼XPRESSION STA DIREC─F├HAR CPX #0 BEQ + JSR DIREC─F╙TRING JMP DIREC─F├ONT + JSR EVALUATE┼XPRESSION BCS ++ LDX DIREC─F╙IZE - CPX #4 BCS ++ LDA ID╓AL,X BNE + INX BNE - + LDA #ERR╓ALUE╘OO╠ARGE JMP ERROR + LDA #1 LDY #0 STA DIREC─F├OUNT+0 STY DIREC─F├OUNT+1 JSR DIREC─F╨UT DIREC─F├ONT = * LDA DIREC─F├HAR CMP #"," BEQ DIREC─F╬EXT CMP #CHR├╥ BEQ + JMP SYNTAX┼RROR + RTS DIREC─F╙TR╨OS .BUF 1 DIREC─F╙TRING = * LDA #0 STA DIREC─F╙TR╨OS STA ID╘YPE STA ID╓AL+1 STA ID╓AL+2 STA ID╓AL+3 - LDX DIREC─F╙TR╨OS CPX STRING╠EN BCC + RTS + LDA STRING┬UF,X STA ID╓AL+0 LDA #1 LDY #0 STA DIREC─F├OUNT+0 STY DIREC─F├OUNT+1 JSR DIREC─F╨UT INC DIREC─F╙TR╨OS JMP - DIREC─F├OUNT .BUF 2 DIREC─F╨UT = * ;(ADDRESS++, ID╓AL, ID╘YPE, DIREC─F╙IZE, DIREC─F├OUNT--, EXP┬UF) LDA DIREC─F├OUNT+0 ORA DIREC─F├OUNT+1 BNE + RTS ;** DEBUG INFORMATION + BIT DEBUG BPL +++ LDA #<DIREC─F╨UT═SG1 LDY #>DIREC─F╨UT═SG1 JSR PUTS LDA ADDRESS+1 JSR PUTHEX LDA ADDRESS+0 JSR PUTHEX LDA #<DIREC─F╨UT═SG2 LDY #>DIREC─F╨UT═SG2 JSR PUTS BIT ID╘YPE BPL + LDA #"?" JSR PUTCHAR JMP ++ + LDX #ID╓AL JSR PUTNUM + LDA #CHR├╥ JSR PUTCHAR ;** HANDLE UNRESOLVED REFERENCE + BIT ID╘YPE BPL + LDX DIREC─F╙IZE LDA #0 JSR ADD═EMORY╚OLE ;** HANDLE RESOLVED REFERENCE + LDX #3 - LDA ID╓AL,X STA MEM╨UT╓ALS,X DEX BPL - LDA DIREC─F╙IZE LDX ADDRESS+0 LDY ADDRESS+1 JSR MEM╨UT ;** ADD RELOCATABLE REFERENCE LDA ID╘YPE BEQ + CMP #$04 BCS + LDX ADDRESS+0 LDY ADDRESS+1 JSR RECORD╥ELOC╥EF ;** GO ONTO NEXT PUT + CLC LDA ADDRESS+0 ADC DIREC─F╙IZE STA ADDRESS+0 BCC + INC ADDRESS+1 BNE + LDA #ERR┴DDRESS╫RAP JMP ERROR + LDA DIREC─F├OUNT+0 BNE + DEC DIREC─F├OUNT+1 + DEC DIREC─F├OUNT+0 JMP DIREC─F╨UT DIREC─F╨UT═SG1 = * .ASC "DEFINE-PUT: ADDRESS=$" .BYTE 0 DIREC─F╨UT═SG2 = * .ASC ", VALUE=" .BYTE 0 DIREC┬UF = * BIT ORIGIN╙ET BMI + LDA #ERR╧RIGIN╬OT╙ET JMP ERROR + LDA #0 JSR PARSE┼XPRESSION CMP #CHR├╥ BEQ + JMP SYNTAX┼RROR + JSR EVALUATE┼XPRESSION BCC + LDA #ERR╬OT╥ESOLVED┼XPR JMP ERROR + LDA ID╓AL+2 ORA ID╓AL+3 BEQ + LDA #ERR╓ALUE╘OO╠ARGE JMP ERROR + LDA ID╓AL+0 LDY ID╓AL+1 STA DIREC─F├OUNT+0 STY DIREC─F├OUNT+1 + LDA #0 STA ID╘YPE STA ID╓AL+0 STA ID╓AL+1 STA ID╓AL+2 STA ID╓AL+3 LDA #1 STA DIREC─F╙IZE JSR DIREC─F╨UT RTS DIREC╔NCLUDE = * DIREC╔F = * DIREC┼LSIF = * DIREC┼LSE = * DIREC┼NDIF = * DIREC═ACRO = * DIREC┼NDMACRO = * DIREC┼XPORT = * LDA #ERR╬OT╔MPLEMENTED JMP ERROR DIREC┬SS = * BIT ORIGIN╙ET BPL + LDA #ERR╧RIGIN╬OT╙ET JMP ERROR + NOP LDA #ERR╬OT╔MPLEMENTED JMP ERROR ;======== ERROR HANDLER ======== ERROR├ODE .BUF 1 ERROR╨OS .BUF 1 ERROR┼XIT├ODE = ACE┼XIT─ATA+0 ;$FC8A09CB:EDITOR-REPOS ERROR┼XIT╠INE = ACE┼XIT─ATA+4 ERROR┼XIT├OL = ACE┼XIT─ATA+8 ERROR┼XIT╥EPOS = ACE┼XIT─ATA+12 ERROR┼XIT╞ILEP = ACE┼XIT─ATA+13 ERROR┼XIT╥ESER = ACE┼XIT─ATA+14 ERROR┬UF = ACE┼XIT─ATA+15 ERROR╥EF = * JSR ERROR╨RERAMBLE LDA #<ERROR═SG2 LDY #>ERROR═SG2 JSR ERROR├AT LDX #3 - LDA EXP╙RC╠INE,X STA WORK+0,X LDA EXP╙RC╞ILE,X STA WORK+4,X DEX BPL - LDA EXP╙RC├OL LDX #WORK+0 LDY #WORK+4 JSR ERROR─ISP╞ILE JMP ERROR╔N ERROR╨RERAMBLE = * STA ERROR├ODE LDX #14 - LDA ERROR┼XIT╚EAD,X STA ERROR┼XIT├ODE,X DEX BPL - LDA #0 STA ERROR╨OS LDA #<ERROR═SG1 LDY #>ERROR═SG1 JSR ERROR├AT LDX #SOURCE╠INE LDY #FILE╨TR LDA SOURCE├OL JMP ERROR─ISP╞ILE ERROR = * JSR ERROR╨RERAMBLE ERROR╔N = * LDX ERROR╨OS LDA #" " STA ERROR┬UF,X INC ERROR╨OS LDA ERROR├ODE ASL TAX LDA ERR─ESC+1,X TAY LDA ERR─ESC+0,X JSR ERROR├AT LDA ERROR├ODE CMP #ERR╒NRESD╥EFERENCES BNE + LDA #<SYM╬AME LDY #>SYM╬AME JSR ERROR├AT + LDA #<ERROR┬UF LDY #>ERROR┬UF JSR EPUTS LDA #CHR├╥ LDX #STDERR JSR PUTC LDA #1 LDX #0 JMP EXIT ERR─ISP╞I╞P .BUF 1 ERR─ISP╞I├OL .BUF 1 ERR─ISP╞I╠IN .BUF 1 ERROR─ISP╞ILE = * ;( .╪=ZP╠INE╧FF, .┴=COL, .┘=ZP╞ILE╨TR, ERROR╨OS ) : ERROR╨OS ;** USES NAME INSTEAD OF FILE╨TR FOR NOW ;** PRODUCES OUTPUT OF THE FORM: ("FILENAME":1234:12) STA ERR─ISP╞I├OL STX ERR─ISP╞I╠IN STY ERR─ISP╞I╞P LDX ERROR╨OS LDA #"(" STA ERROR┬UF,X INX LDA #CHR╤UOTE STA ERROR┬UF,X INX STX ERROR╨OS LDA NAME+0 LDY NAME+1 JSR ERROR├AT LDA #CHR╤UOTE STA ERROR┬UF,X INX LDA #":" STA ERROR┬UF,X INX STX ERROR╨OS LDX ERR─ISP╞I╠IN JSR ERROR─ISP╞ILE┴PNUM LDA #":" STA ERROR┬UF,X INX STX ERROR╨OS LDA ERR─ISP╞I├OL STA NUMBER+0 LDA #0 STA NUMBER+1 STA NUMBER+2 STA NUMBER+3 LDX #NUMBER JSR ERROR─ISP╞ILE┴PNUM LDA #")" STA ERROR┬UF,X INX STX ERROR╨OS RTS ERROR─ISP╞ILE┴PNUM = * ;( .╪=ZPOFF, ERROR╨OS ) : .╪=ERROR╨OS LDA #<PUTNUM╬UM LDY #>PUTNUM╬UM STA ZP+0 STY ZP+1 LDA #1 JSR UTOA LDA #<PUTNUM╬UM LDY #>PUTNUM╬UM ;** FALL THROUGH ERROR├AT = * ;( .┴┘=STR, ERROR╨OS ) : .╪=ERROR╨OS STA WORK+14 STY WORK+15 LDX ERROR╨OS LDY #0 - LDA (WORK+14),Y STA ERROR┬UF,X BEQ + INX INY BNE - + STX ERROR╨OS RTS ERROR┼XIT╚EAD = * .BYTE $FC,$8A,$09,$CB,$00,$00,$00,$00,$00,$00,$00,$00,$FF,$06,$00 ERROR═SG1 = * .ASC "ERR " .BYTE 0 ERROR═SG2 = * .ASC ", REF" .BYTE 0 ERR─ESC .WORD ERR00,ERR01,ERR02,ERR03,ERR04,ERR05,ERR06,ERR07,ERR08,ERR09 .WORD ERR10,ERR11,ERR12,ERR13,ERR14,ERR15,ERR16,ERR17,ERR18,ERR19 .WORD ERR20,ERR21,ERR22,ERR23,ERR24,ERR25,ERR26 ERR00 .ASC "╧K--NO ERROR" .BYTE 0 ERR01 .ASC "┴N IDENTIFIER TOKEN EXCEEDS 240 CHARS IN LENGTH" .BYTE 0 ERR02 .ASC "┴ STRING LITERAL EXCEEDS 240 CHARS IN LENGTH" .BYTE 0 ERR03 .ASC "╥AN INTO A ├╥ BEFORE END OF STRING LITERAL" .BYTE 0 ERR04 .ASC "╔NVALID NUMERIC LITERAL" .BYTE 0 ERR05 .ASC "╬UMERIC LITERAL VALUE OVERFLOWS 32-BITS" .BYTE 0 ERR06 .ASC "╙YNTAX ERROR" .BYTE 0 ERR07 .ASC "┴TTEMPT TO PERFORM NUMERIC OPERATORS ON A STRING" .BYTE 0 ERR08 .ASC "┼XPRESSION HAS MORE THAN 17 OPERANDS" .BYTE 0 ERR09 .ASC "╥AN OUT OF MEMORY DURING COMPILATION PROCESS" .BYTE 0 ERR10 .ASC "┴TTEMPT TO REDEFINE A SYMBOL" .BYTE 0 ERR11 .ASC "┴TTEMPT TO ASSEMBLE CODE WITH CODE ORIGIN NOT SET" .BYTE 0 ERR12 .ASC "╔NTERNAL ERROR: ATTEMPT TO ASSIGN TO UNEXPECTED ID" .BYTE 0 ERR13 .ASC "╬ON-NUMERIC SYMBOL IN A NUMERIC EXPRESSION" .BYTE 0 ERR14 .ASC "┼XPECTING AN OPERATOR" .BYTE 0 ERR15 .ASC "┼XPECTING AN OPERAND" .BYTE 0 ERR16 .ASC "┼XPECTING A COMMAND" .BYTE 0 ERR17 .ASC "╓ALUE IS TOO LARGE OR NEGATIVE" .BYTE 0 ERR18 .ASC "┬RANCH OUT OF RANGE" .BYTE 0 ERR19 .ASC "╞EATURE IS NOT (YET) IMPLEMENTED" .BYTE 0 ERR20 .ASC "╔NSTRUCTION DOES NOT SUPPORT GIVEN ADDRESS MODE" .BYTE 0 ERR21 .ASC "┴DDRESS WRAPED AROUND 64╦ CODE ADDRESS SPACE" .BYTE 0 ERR22 .ASC "┼RROR TRYING TO WRITE OUTPUT OBJECT FILE" .BYTE 0 ERR23 .ASC "─IRECTIVE REQUIRES RESOLVED EXPRESSION" .BYTE 0 ERR24 .ASC "├ODE ORIGIN ALREADY SET; YOU CAN'T SET IT TWICE" .BYTE 0 ERR25 .ASC "╒NRESOLVED SYMBOL: " .BYTE 0 ERR26 .ASC "╘HUS ASSEMBLER DOESN'T ACCEPT .DOT COMMANDS, ┬UDDY!" .BYTE 0 WPUTNUM = * LDA #STDOUT STA PUTNUM╞D JMP PUTNUM╔N EPUTNUM = * LDA #STDERR JMP FPUTNUM PUTNUM = * LDA #STDOUT FPUTNUM = * STA PUTNUM╞D LDY #1 PUTNUM╔N = * LDA #<PUTNUM╬UM STA ZP+0 LDA #>PUTNUM╬UM STA ZP+1 TYA JSR UTOA LDX PUTNUM╞D JMP FPUTS┌P PUTNUM╞D .BUF 1 PUTNUM╬UM .BUF 11 PUTHEX = * ;( .┴=VALUE ) LDX #STDOUT FPUTHEX = * ;( .┴=VALUE, .╪=FD ) STX PUTNUM╞D PHA LSR LSR LSR LSR TAX LDA PUTHEX├HARS,X LDX PUTNUM╞D JSR PUTC PLA AND #$0F TAX LDA PUTHEX├HARS,X LDX PUTNUM╞D JSR PUTC RTS PUTHEX├HARS = * .ASC "0123456789ABCDEF" CHECK╙TOP = * JSR STOPKEY BCS + RTS + LDA #<STOPPED═SG LDY #>STOPPED═SG JSR EPUTS LDA #1 LDX #0 JMP EXIT STOPPED═SG = * .ASC "<╙TOPPED>" .BYTE CHR├╥,0 ;======== UTILITY FUNCTIONS ======== INC╠ONG = * ;( .╪=ZP╧FFSET ) INC 0,X BNE + INC 1,X BNE + INC 2,X BNE + INC 3,X + RTS DEC╠ONG = * ;( .╪=ZP╧FFSET ) SEC LDA 0,X SBC #1 STA 0,X INX LDY #3 - LDA 0,X SBC #0 STA 0,X INX DEY BNE - RTS ;======== INCLUDED FILES ======== .SEQ ASHELP.S ;======== BSS ======== BSS = * SOURCE┬UF = BSS+0 ;( 256 BYTES) STRING┬UF = SOURCE┬UF+256 ;( 256 BYTES) SYM┬UF = STRING┬UF+256 ;( 256 BYTES) SYM╬EXT = SYM┬UF+0 SYM╓ALUE = SYM┬UF+4 SYM╒NRES╧PND = SYM┬UF+8 SYM╘YPE = SYM┬UF+9 SYM├LASS = SYM┬UF+10 SYM╬AME╠EN = SYM┬UF+11 SYM╬AME = SYM┬UF+12 SYM╚ASH = SYM┬UF+254 EXP╘ABLE = SYM┬UF+256 ;( 256 BYTES == 15 ENTRIES) EXP╚OLE╘YPE = EXP╘ABLE+0 EXP╠ENGTH = EXP╘ABLE+1 EXP╒NRES├NT = EXP╘ABLE+2 EXP╙RC├OL = EXP╘ABLE+3 EXP╚OLE┴DDR = EXP╘ABLE+4 EXP╙RC╠INE = EXP╘ABLE+8 EXP╙RC╞ILE = EXP╘ABLE+12 EXP╞IELD = EXP╘ABLE+0 EXP╧P = EXP╞IELD+0 EXP╘YPE = EXP╞IELD+1 EXP╙IGN = EXP╞IELD+2 EXP╚I╠O = EXP╞IELD+3 EXP╓ALUE = EXP╞IELD+4 EXP╬EXT╒NRES = EXP╞IELD+8 EXP╬EXT╧PND = EXP╞IELD+12 EXP╥ESERVED = EXP╞IELD+13 IDENT╚ASH╘ABLE = EXP╘ABLE+256 ;(4096 BYTES == 1024 ENTRIES (REF:H╘AB╨AG) MEM╨TR╘ABLE = IDENT╚ASH╘ABLE+4096 ;( 256 BYTES == 64 ENTRIES) MEM┬UF = MEM╨TR╘ABLE+256 ;( 256 BYTES) WRITE╬AME = MEM┬UF+256 ;( 20 BYTES) TPA╞REEMAP = WRITE╬AME+20 ;( 256 BYTES) BSS┼ND = TPA╞REEMAP+256