C/C++ Users Group Library 1996 July

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================================================================== EEEEEEE MM MM IIIIIII L Y Y 5555555 22222 E M M M M I L Y Y 5 2 2 E M M M I L Y Y 555555 2 EEEE M M I L Y --- 5 22222 E M M I L Y 5 2 E M M I L Y 5 5 2 EEEEEEE M M IIIIIII LLLLLLL Y 55555 2222222 ================================================================== A Simulator/Emulator for the 8051 and 8052 Release 1.3 Revised 04-Jan-94 Copyright 1991-1994 Dave Dunfield All rights reserved EMILY: An 8051/52 simulator Page: 1 1. INTRODUCTION EMILY is a software simulator for the 8051 and 8052 families of processors. It provides a powerful debugging environment, offering many features: - Supports full 64K of PROGRAM and 64K of DATA memory. DATA and PROGRAM memory may also be overlapped into a single 64K address space. - Hardware emulation mode communciates with the target system, and allows you to include the physical I/O lines, timers etc. in your simulation. - Single step, Multi Step, Animate and Full Speed execution modes. - Simultanious on-screen displays of program disassembly, internal memory, CPU registers and simulation messages. - Full screen editors for CPU registers, Special Function Registers (SFR's), and each of the INTERNAL, EXTERNAL DATA and PROGRAM memory spaces. All of the above may be viewed/altered at any time during the debugging session. - Multiple breakpoints are transparent to the user program. - Supports the additional SFR's and internal RAM of the 8052 series. 1.1 System Requirements EMILY will run on any IBM PC/AT/PS2 compatible system with a MDA/CGA/EGA or VGA display, two COMM ports, and at least 192K of free system RAM. - If hardware emulation or serial I/O are not used, only one COMM port is required. - If Overlapped data/program memory is used, only 128K of free ram is required. - Some CGA displays may exibit "snow" or flicker during high speed screen updates. This effect will not occur with MDA, EGA or VGA displays. EMILY: An 8051/52 simulator Page: 2 2. STARTING UP EMILY If you are using the optional hardware emulation mode, insure that the resident control software (supplied) is inserted into the target system, and that the PC running EMILY is connected to the target systems serial port via COM2. Power on the test system before starting EMILY. The resident control software must be active when EMILY "looks" for it. EMILY is invoked by typing her name at the DOS command line. You will be greeted with a "welcome" screen which displays a reminder of the command line syntax and the copyright message. This screen will remain on the display for about 5 seconds (10 seconds in the demo version). Pressing any key while this screen is visible will bypass this delay, and proceed directly to the main control panel. If EMILY is given a file name on the command line, she loads it in the same manner as if the 'L'oad command had been used from within the main control panel. EMILY: An 8051/52 simulator Page: 3 EMILY also accepts several option switches on the command line: /Hardware[:n] - Enables the hardware emulation feature to cause EMILY to interact with the target system when performing I/O accesses. This option may be followed by a ':' and a numeric value which defines the BAUD RATE to be used to communicate with the target system. Default is 28800. /Mono * - Inhibits the color display, even if a color adapter is present. This option may be useful if your monitor/adapter combination provides an unpleasent or unusable display for EMILY. /Overlap - Joins EXTERNAL DATA and PROGRAM memory into a single 64K address space which can be accessed with either MOVX or MOVC. This is equivalent to a hardware implementation in which the PSEN and RD signals are ANDed together. /Reset - Causes EMILY to de-assert the RTS line when she initializes the serial port. This option may be required when using EMILY with older versions of our "BD52" single board computer. /Swapcom - Exchanges the operation of the two serial ports on the PC. When this option is used, COM1 will be used to communicate with the target system, and COM2 is used for serial I/O redirection. * Note: If some of the EMILY windows appear to be an un-readable washed-out yellow color, try adjusting the color contrast on your monitor. Those windows should be an easy to read brown. If you are using the '/Hardware' option, and EMILY is unable to establish communication with the target system, you will see an error message flashing on the screen. EMILY will keep trying, allowing you to debug the connection. You may also press the ESCAPE key to disable hardware emulation, and proceed with a software only simulation. EMILY: An 8051/52 simulator Page: 4 3. USING EMILY 3.1 The Main Control Panel Once EMILY is up and running, you will be presented with the "Main Control Panel", which consists of four "windows" displaying: - A disassembly of program memory (Upper LEFT) - The contents of CPU registers (Upper CENTER) - The contents of INTERNAL MEMORY (Upper RIGHT) - Informational messages from EMILY (Lower portion) All of EMILY'S functions are accessed by command characters entered from this screen: 3.1.1 A - Animate execution This function begins execution of the user program (from the address in the PC register). As each instruction is executed, EMILY will display the instruction being executed, the CPU registers, and the contents of internal RAM in the appropriate windows. When you enter the 'A' command, EMILY will prompt you for the number of instructions to animate. Pressing return (without entering a number) will cause the animation to proceed non-stop. Pressing <escape> will return you to the Main Control Panel. The animation will terminate when: - The requested number of instructions have been stepped. - A breakpoint is encountered. - The illegal opcode ($A5) is encountered. - The <escape> key is pressed on the PC console. 3.1.2 B - set Breakpoint This command sets a breakpoint such that program execution under the 'A'nimate, or 'G'o, commands will stop when the breakpoint address is encountered. Up to 10 breakpoints may be in effect at the same time. You will be prompted for the address (in HEX). Pressing return (without entering an address) will cause the breakpoint to be set at the current program counter (PC) location. Pressing <escape> will return you to the main control panel. EMILY stores the breakpoint addresses internally in a simple zero terminated list. This allows her to avoid searching a fixed size table, and helps speed up the operation of the program, especially when there are few breakpoints. This does however cause the restriction that you cannot set a breakpoint at address zero ($0000). EMILY: An 8051/52 simulator Page: 5 3.1.3 C - Change register You will be prompted for the CPU register to change. Enter a character from the following list, ESCAPE to abort, or F1 for a reminder: A - A accumulator B - B accumulator D - Data pointer (DPTR) S - Stack pointer P - Program counter W - processor status Word 0-7 - general register 0-7 After you have selected the register, you will be prompted for the new contents (in HEX). 3.1.4 D - edit Data memory This command allows you to edit EXTERNAL DATA memory using EMILY's built in memory editor. See the "Memory Editor" section. 3.1.5 F - display/edit special Function registers The names and contents of all SFR's are displayed in a menu. To change a register, enter the character preceeding the ':', immediately to the left of its name. You will be prompted for its new contents. If multiple columns of SFR's are defined, use <space> to select the column to edit. When debugging with the hardware emulation option, the values read/and written to the SFR's will reflect the actual state of the hardware lines etc. on the target system board. Pressing any key while in this menu will refresh the display, and make visible any changes which have occured on the target system I/O lines etc. When debugging without the hardware emulator option, SFR's are simply stored internaly within EMILY's memory. EMILY: An 8051/52 simulator Page: 6 3.1.6 G - Go: execute program This function begins high-speed execution of the user program (from the address in the PC register). When you enter the 'G' command, EMILY will prompt you for the number of instructions to execute. Pressing return (without entering a number) will cause the program to proceed non-stop. Pressing <escape> will return you to the Main Control Panel. Program execution will terminate when: - The requested number of instructions have been executed. - A breakpoint is encountered. - The illegal opcode ($A5) is encountered. - The <escape> key is pressed on the PC console. * * NOTE: If you are using 'Local' serial I/O mode, ESCAPE offers you a menu of execution I/O functions. See the F3 command for more information. 3.1.7 I - edit Internal memory This command allows you to edit INTERNAL memory using EMILY's built in memory editor. See the "Memory Editor" section. 3.1.8 J - Jump to PC This command re-positions the disassembly display window (if necessary) to display the instruction addressed by the current CPU Program Counter (PC). 3.1.9 K - Kill all breakpoints Removes ALL breakpoints after prompting for permission to do so. 3.1.10 L - Load program image Prompts for the name of a file, and loads it into PROGRAM memory. The file must be in either INTEL or MOTOROLA hex download format. 3.1.11 N - Next disassembly window Advances the disassembler to display the following screen. Subsequent 'N' commands will proceed to disassemble higher memory addresses. 3.1.12 P - edit Program memory This command allows you to edit PROGRAM memory using EMILY's built in memory editor. See the "Memory Editor" section. EMILY: An 8051/52 simulator Page: 7 3.1.13 R - Remove a breakpoint Prompts for the address, and if a breakpoint is set at that address, it is removed. Pressing return (without entering an address) will remove the breakpoint at the current program counter (PC) location. 3.1.14 T - Traceback viewer In all execution modes, EMILY keeps track of the last 4095 instructions executed. By entering the traceback viewer, you can examine this recording, and determine program activity up to 4095 instructions preceeding the one on which execution last stopped. The following command keys are available in the viewer: Up - Backup the display 1 instruction. Down - Advance the display 1 instruction. PgUp - Backup the display 50 instructions. PgDn - Advance the display 50 instructions. Home - Position to the beginning of recording. End - Position to the end of recording. F1 - Display a help summary. F2 - Prompt for position & move. F3 - Search backward (in time) for address. * F4 - Search forward (in time) for address. * Esc - Exit the Traceback viewer. * If you press <return> without entering an address, the search commands will look for the previous or next instance of the instruction at your current position in the traceback buffer. Only the instruction executed is saved in the traceback viewer, the contents of registers, RAM etc. are not recorded. The instruction at position 0 in the traceback buffer is the one to which the current PC points, and has not yet been executed. 3.1.15 V - Vector to interrupt This function prompts you with a menu of the available 8052 interrupts. Use the arrow keys to position the cursor bar to the interrupt you desire to simulate, and press ENTER to select it. You may use ESCAPE to cancel the function and return to the Main Control Panel. EMILY will simulate a long call (LCALL) to the corresponding interrupt vector address by saving the current Program Counter on the CPU stack, and reloading it with the vector. Any SFR bits normally set when the particular interrupt occurs will be set at this time. EMILY: An 8051/52 simulator Page: 8 3.1.16 F1 - Help display Pressing this key displays a summary of the EMILY commands which are available from the Main Control Panel. 3.1.17 F2 - Set Disassembler Address Prompts for an address (in HEX), and re-positions the disassembler window to display instructions beginning at that address. 3.1.18 F3 - Setup Serial Port Opens a window displaying the (B)audrate, (P)arity, (D)ata bits and (S)top bits which are currently configured for the PC's COM1 serial port. Press B, P, D or S to cycle to the next corresponding entry. When Baudrate is selected as 'Local', EMILY will re-direct the programs serial accesses to the message window. Any characters which are written to SBUF will be output in the message window, and any character which are typed at the keyboard will appear as incomming serial data. When this mode is active, Pressing ESCAPE in the 'G'o command brings up a menu of execution options: End simulation - Stops the 'G'o command. Send ESCAPE - Send ESCAPE through as a charcter. Zoom window - Switch to full screen I/O window. If 'Local' is not selected, EMILY re-directs the programs serial accesses to the PC's COM1 serial port, however, for maximum flexibility, the actual data format used may be configured by this menu. EMILY allows you to "fine tune" a baud rate, by using the Up/Down keys. Note that the available baud rate values are determined by the PC COMM port hardware, and may not fall exactly on the value you wish to use. Asynchronous communication is specified to work properly as long as the device is operating within 5% of the intended baud rate. For example: Desired baud rate : 1500 Allowable range (+/- 5%): 1425-1575 Closest PC baud rate : 1496 In the above example, the baud rate produced is within 0.3% of the desired value, and is therefore well within specifications. EMILY: An 8051/52 simulator Page: 9 3.1.19 <space> - Single step one instruction Every time you press the <space> bar, EMILY will execute one instruction, and update the on-screen displays. 3.1.20 PgDn - Advance IRAM display page Pressing this key advances the internal memory display window by one page (64 bytes). 3.1.21 PgUp - Backup IRAM display page Pressing this key backs up the internal memory display window by one page (64 bytes). 3.1.22 Down - Advance IRAM display line Pressing the "down arrow" key advances the internal memory display window by one line (4 bytes). 3.1.23 Up - Backup IRAM display line Pressing the "up arrow" key backs up the internal memory display window by one line (4 bytes). EMILY: An 8051/52 simulator Page: 10 3.2 The Memory Editor When you activate the 'D', 'I' or 'P' commands from the main control panel, EMILY will invoke its internal "Memory Editor" to access the desired memory area. When you are within this editor, the following commands are available: 3.2.1 F1 - Help display Pressing this key displays a summary of the EMILY commands which are available from within the Memory Editor. 3.2.2 F2 - Set Edit Address Prompts for an address (in HEX), and re-positions the editor display and cursor to edit at that address. 3.2.3 F3 - Toggle Edit Mode EMILY allows two edit modes, HEX and ASCII. When in HEX mode, your cursor will be positioned in the hexidecimal display portion of the memory memory dump, allowing you to change memory by entering a new value as two hexidecimal characters. When in ASCII mode, your cursor will be positioned over the ASCII portion of the dump, and you can replace memory with ASCII text typed at the keyboard. Pressing F3 will toggle between HEX and ASCII mode, causing your cursor to switch between the corresponding portion of the memory display. 3.2.4 Up - Move up 1 line Pressing the UP ARROW causes the cursor to move upwards on the screen by one line. This reduces the memory edit address by 16 bytes. 3.2.5 Down - Move down 1 line Pressing the DOWN ARROW causes the cursor to move downwards on the screen by one line. This increases the memory edit address by 16 bytes. 3.2.6 Left - Move left 1 byte Pressing the LEFT ARROW causes the cursor to move to the left by one byte position. This reduces the memory edit address by 1 byte. If the cursor is already at the left hand margin, it will wrap around to the rightmost position of the previous line. EMILY: An 8051/52 simulator Page: 11 3.2.7 Right - Move right 1 byte Pressing the RIGHT ARROW causes the cursor to move to the right by one byte position. This in increases the memory edit address by 1 byte. If the cursor is already at the right hand margin, it will wrap around to the leftmost position of the following line. 3.2.8 PgUp - Move back 1 page Pressing the PGUP key causes the editor to move back one display page. This reduces the memory edit address by 256 bytes. 3.2.9 PgDn - Move forward 1 page Pressing the PGDN causes the editor to move forward one display page. This increases the memory edit address by 256 bytes. 3.2.10 Home - Move to start of line Pressing the HOME key causes the cursor to move to the leftmost position of the line it is currently on. If the cursor was already in the leftmost position, it is moved to the leftmost position of the preceeding line. 3.2.11 End - Move to end of line Pressing the END key causes the cursor to move to the rightmost position of the line it is currently on. If the cursor was already in the rightmost position, it is moved to the rightmost position of the following line. 3.2.12 Ctrl-PgUp - Move to start of memory Pressing the CTRL and PGUP keys re-positions the editor display and cursor to address $0000 at the start of the memory block. 3.2.13 Ctrl-PgDn - Move to end of memory Pressing the CTRL and PGDN keys re=positions the editor display and cursor to the highest address available in the memory block. EMILY: An 8051/52 simulator Page: 12 3.3 Hardware Emulation EMILY supports a hardware emulation mode, which provides access to most of the physical I/O ports, timers etc. from the target system in your simulation. The target system must be running the supplied control software, which interacts with EMILY, and perform the I/O accesses upon her commands. The serial port of the target system must be connected to the COM2 serial port of the PC. There are a few restrictions which apply: - The target system must provide access to the CPU serial port. - There is an approximatly 0.7 MS delay when accessing the I/O ports and other physical hardware. This occurs due to the serial activity required to communicate the data to and from the target system. For most applications, this delay is acceptable, particularly in the stop/start environment of simulation and debugging. NOTE: If you are using a baudrate to communicate with the target system which is lower than the default (28800), this delay will be longer. - The control software uses TIMER1 internally to generate the baud rate clock for its serial port. This means that TIMER1 is unavailable during the simulation. If your application uses the serial port, we recommend you also use TIMER1 as the baud rate generator. Since EMILY has a separate setup memu for serial port speed, parity etc. It will not affect your program that TIMER1 is disabled during the simulation. Simply press F3 at EMILY's main control panel, and select the serial parameters you desire. EMILY: An 8051/52 simulator Page: 13 When using this (Hardware Emulation) feature, the Resident Control Firmware should be running in the target system BEFORE executing EMILY. Be sure to specify '/H:<speed>' parameter on the command line when starting EMILY. The value of <speed> depends on the target systems operating frequency. The following table shows the speeds which can be used with several common crystal frequencies without modifying the supplied Resident Control Firmware: Freq (Mhz) Speed -> Actual ---------------------------------------- 11.0592 28800 -> 28800 0.0% 11.0 28646 -> 28800 0.5% 9.0 23438 -> 23040 1.7% 7.3728 19200 -> 19200 0.0% 5.0 13020 -> 12800 1.7% 4.0 10417 -> 10473 0.5% 3.68 9600 -> 9600 0.0% 3.59 9349 -> 9600 2.7% 3.0 7813 -> 7680 1.7% 2.0 5208 -> 5236 0.5% 1.84 4800 -> 4800 0.0% 1.0 2604 -> 2618 0.5% At the beginning of the supplied KERNAL.ASM file is a large comment which describes how to change the baud rate constant to obtain other serial port speeds. The following table shows speeds which can be used with other common crystal frequencies by altering the "BAUD" value in the KERNAL.ASM file: Freq (Mhz) BAUD Value Speed -> PC Speed ------------------------------------------------ 12.0 3 10417 -> 10473 0.5% 10.0 2 13020 -> 12800 1.7% 8.0 2 10417 -> 10473 0.5% 7.0 2 9116 -> 8862 2.8% 6.0 2 7813 -> 7680 1.7% EMILY: An 8051/52 simulator Page: 14 3.4 Messages During the course of operation, EMILY may display the following messages in the message window located in the lower portion of the screen: 3.4.1 All Used! You have tried to enter a breakpoint, when all available breakpoints are in use. EMILY allows up to 10 code breakpoints to be active at any one time. 3.4.2 Animating at XXXX Indicates that EMILY has commenced animated execution of your program, beginning at the address 'XXXX'. 3.4.3 Already set! Issued to indicate that the address at which you have tried to set a breakpoint is already active as a breakpoint. This message will also result of you attempt to set a breakpoint at address zero ($0000). 3.4.4 Breakpoints: [XXXX ...] This message shows the currently set breakpoint addresses, and is issued whenever any command involving breakpoints is performed. 3.4.5 Executing at XXXX Indicates that EMILY has commenced full speed exection of your program, beginning at the address 'XXXX'. 3.4.6 Code and data are overlapped This message results from the use of the '/Overlap' switch on the EMILY command line, and indicates that the external CODE and DATA memory address spaces are combined into a single overlapping 64K segment. 3.4.7 Code and data are separate Indicate that EMILY has established separate 64K memory address spaces for the code and data, resulting in 128K total external memory. 3.4.8 FILENAME: Bad checksum EMILY has encountered a record containing a incorrect checksum value while attempting to 'L'oad the named file. EMILY: An 8051/52 simulator Page: 15 3.4.9 FILENAME: Demo limit exceeded! This message occurs only in the "Demonstration" version of EMILY, and indicates that you have attempted to 'L'oad more than 500 bytes of code. The demonstration release is intended only to allow you to check out EMILY's features, you must purchase the "production" version if you intend to use the program for serious development and debugging. 3.4.10 FILENAME: Invalid HEX record EMILY has encountered an improperly formatted download record while attempting to 'L'oad the named file. 3.4.11 FILENAME: N bytes loaded The indicated number of bytes have been successfully 'L'oaded from the named file. 3.4.12 FILENAME: Unable to access EMILY was unable to open and read the named file. 3.4.13 Hardware emulation is disabled Indicates that the EMILY is running as a software only simulator, and will emulate special functions registers etc. using internal RAM memory. 3.4.14 Hardware emulation is enabled Issued if the "/Hardware" switch was used on the EMILY command line, and the Resident Control Software in the target system has been detected. In this mode of operation, special function register accesses are communicated to the control software, and result in physical activity on the target system. 3.4.15 Stopped at XXXX Indicates that EMILY has stopped execution of you program at the indicated address. This message is appended to the initial message indicating that execution had commenced. 3.4.16 Target system is not responding!!! Indicates that the "/Hardware" option switch was used on the EMILY command line, but EMILY cannot establish communication with the target system. EMILY will keep trying, allowing you to attempt to debug the connection. You may also press the ESCAPE key, to disable hardware emulation mode, and proceed with a software only simulation. EMILY: An 8051/52 simulator Page: 16 3.4.17 XXXX: Not found This message is issued while in the 'T'raceback viewer, to indicate that an address 'XXXX' you have searched for does not occur between your current position, and the start/end of the traceback buffer. EMILY: An 8051/52 simulator TABLE OF CONTENTS Page 1. INTRODUCTION 1 1.1 System Requirements 1 2. STARTING UP EMILY 2 3. USING EMILY 4 3.1 The Main Control Panel 4 3.2 The Memory Editor 10 3.3 Hardware Emulation 12 3.4 Messages 14