6809 Simulator/Emulator ======================= sbc09 stands for Lennart Benschop 6809 Single Board Computer. It contains a assembler and simulator for the Motorola M6809 processor. copyleft (c) 1994-2014 by the sbc09 team, see AUTHORS for more details. license: GNU General Public License version 2, see LICENSE for more details. Forum thread: http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=8&t=4880 Project: https://github.com/6809/sbc09 For the usage of the assembler a09 and 6809 single board system v09 read doc/sbc09.creole! This distribution includes two different kinds of simulators: 1. The old sim6809 based "simple" simulator built as v09s, v09st 2. The 6809 single board system as a stand alone environment built as v09 Structure --------- src/ Source for the developement tools and virtual machines ... a09.c The 6809 assembler. It's fairly portable (ANSI) C. It works on both Unix and DOS (TC2.0). Features of the assembler: - generates binary file starting at the first address where code is actually generated. So an initial block of RMB's (maybe at a different ORG) is not included in the file. - Accepts standard syntax. - full expression evaluator. - Statements SET, MACRO, PUBLIC, EXTERN IF/ELSE/ENDIF INCLUDE not yet implemented. Some provisions are already made internally for macros and/or relocatable objects. v09s.c The (old) 6809 simulator. Loads a binary image (from a09) at adress $100 and starts executing. SWI2 and SWI3 are for character output/input. SYNC stops simulation. When compiling set -DBIG_ENDIAN if your computer is big-endian. Set TERM_CONTROL for a crude single character (instead of ANSI line-by-line) input. Works on Unix. v09stc.c Same as v09s.c but for Turbo C. Has its own term control. v09.c engine.c io.c The 6809 single board simulator/emulator v09. mon2.asm Monitor progam, alternative version of monitor.asm (used in ROM image alt09.rom) monitor.asm Monitor progam (used in ROM image v09.rom for v09) makerom.c Helper tool to generate ROM images for v09. basic/ Basic interpreters ... basic.asm Tiny Basic fbasic.asm Tiny Basic with Lennarts floating point routines. doc/ Documentation ... examples/ Several test and benchmark programs, simple routines and some bigger stuff like a Forth system (ef09). ef09.asm Implementation of E-Forth, a very rudimentary and portable Forth. Type WORDS to see what words you have. You can evaluate RPN integer expressions, like "12 34 + 5 * . " You can make new words like " : SQUARED DUP * ; " etc. examples_forth/ Forth environment with examples. For the 6809 single board system. Notes on Linux Fedora Core 6 ---------------------------- 2012-06-04 Compiling v09s, v09st: * BIG_ENDIAN (already used by LINUX itself, changed to CPU_BIG_ENDIAN) Now automatically set according to BIG_ENDIAN and BYTE_ORDER if existing. * If TERM_CONTROL mode is active the keyboard is not really in raw mode - keyboard signals are still allowed. * A tracefilter based on register values can be placed in the TRACE area to get tracing output triggered by special states a09 Assembler ------------- Bugfixes: * addres modes a,INDEXREG b,INDEXREG d,INDEXREG now known as *legal*! Extended version: http://lennartb.home.xs4all.nl/A09.c (see above) * options -x and -s produces output in Intel Binary/Srecord format, contains the above mentioned bugfixes (but fixed by the original author). v09s* Simulator --------------- ### CC register E F H I N Z V C Flag 8 7 6 5 4 3 2 1 Bit | | | | | | | | | | | | | | | +- $01 | | | | | | +--- $02 | | | | | +----- $04 | | | | +------- $08 | | | +--------- $10 | | +----------- $20 | +------------- $40 +--------------- $80 # differences from real 6809: ldd #$0fc9 addb #$40 ; $C9+$40 -> $09 -> C=1 adca #$00 ; $0F+C -> $10 -> H=1 Should Set the half-carry! For this example the half-carry is set on a real 6809, also correctly emulated on the VCC. v09s does the same. According to "Motorola 6809 and Hitachi 6309 Programmer's Reference" the half-carry is only properly set for ADD and ADC (on 8-bit accumulators). For ASR, ASL (= LSL), CMP, SBC, SUB this condition flag is undefined. The v09s simulator calculates the half-carry also for ASR and ASL. ASL does the following: * sets H if bit 4 was set. * clears H if bit was not set. ASR (=LSR) does the following: * xxx1 xxxx --- (LSR|ASR) ---> xxxx 1xxx => H=1 * xxx0 xxxx --- (LSR|ASR) ---> xxxx 0xxx => H=0 But note: LSR never touches the half-carry! ## TFR/EXG with unaligned register sizes See http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=8&t=5512 Points to the 6309 behavior which is not compatible to 6809! tfr x,b ; 6809,6309: b low byte of x, a unchanged tfr x,a ; 6809, a low byte of x, b unchanged ; on a 6309: a high(!) byte of x, b unchanged Might be used to get the low byte out of an index register without harm the A register: instead of pushs a tfr x,d andb #$1f it could be used tfr x,b andb #$1f ; a left untouched! REF: http://www.6809.org.uk/dragon/illegal-opcodes.shtml REF: http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=8&t=4886 tfr a,x ; low byte of x has value of a, high byte is $FF tfr b,x ; low byte of x has value of b, high byte is $FF exg a,x ; low byte of x has value of a, high byte is $FF exg b,x ; low byte of x has value of b, high byte is $FF According to Motorola 6809 and Hitachi 6309 Programmer's Reference Except for the case where the first operand is 8 bit and register CC or DP: In this case the 16-bit register has the value of the 8-bit register in high and low byte! ### special behavior swi2 output character (STDOUT) in register B swi3 read character from keyboard into register B sync exit simulator ### start program v09s BINARY ### start program with tracing output on STDOUT v09st BINARY ### run program and leave memory dump (64k) # memory dump in file dump.v09 v09s -d BINARY ### Bugfixes * static int index; otherwise the global C library function index() is referenced! Write access on it leads to a core dump. * BIG_ENDIAN is not useable in FLAG because (POSIX?) Unix (especially Linux) defines its byte order. If BIG_ENDIAN == BYTE_ORDER -> architecture is big endian! Changed to CPU_BIG_ENDIAN, which is refering BIG_ENDIAN and BYTE_ORDER automatically (if existent). eForth ------ Source: ef09.asm Backspace character changed from 127 to 8. Memory-Layout: 0100 At this address the binary is placed to, the Forth entry point 03C0 USER area start 4000 Memory TOP I/O: Keyboard input: * ^H or BSP deletes character * RETURN -> interrupts (long) output Start: ../v09s ef09 Bugs: SEE ; STAR (*) : * UM* DROP ; ... wrong, : * M* DROP ; ... correct (sign!) Typical commands: Commands alway in upper case!!! WORD list of defined words of the current vocabulary BYE exit Forth (back to shell) DUMP hex memory dump SEE HL-word decompiler, corrected: * stops at EXIT * handles more special primitives (literals, strings, variable, constants)) * handles Direct Threading * output line by line with address .S shows the content of the parameter stack count FOR ... NEXT replacement for hi lo DO ... I ... LOOP hi lo - 1+ FOR ... R@ lo + ... NEXT Extensions: ZEQUAL 0= Primitive PLUS1 1+ Primitive, added 2012-06-07 ROLL ROLL HL, added CONST CONSTANT HL, added doCONST Primitive, added 2012-06-08 TWOSTAR 2* Primtive, added TWOSLASH 2/ Primtive, added MINUS1 1- Primtive, added SWAPHL >< Primtive, added STAR256 256* Primtive, added SLASH256 256/ Primtive, added CMOVE CMOVE Primtive FILL FILL Primtive 2012-06-09 ULESS U< Primitive LESS < Primitive DO DO HL, added QDO ?DO HL, added DODO (DO) Primitive, added DOQDO (?DO) Primitive, added LOOP LOOP HL, added PLOOP +LOOP HL, added DOLOOP (LOOP) Primitive, added DOPLOOP (+LOOP) Primitive, added 2012-06-11 NEGAT NEGATE Primitive, alternative added UMSTA UM* Primitive, but without MUL LSHIFT LSHIFT Primitive, added RSHIFT RSHIFT Primitive, added 2012-06-12 LEAVE LEAVE Primitive, added (fig Forth) MDO -DO HL, added DOMDO (-DO) Primitive, added I I Primitive, added (same as R@) CMOVEW CMOVE Primitive, other implementation STAR * korr.: uses M* (instead UM*) BLANK BL Constant 2012-06-19 USLASH U/ Primitive, same as UM/MOD UM/MOD uses USLASH 2012-06-20 DPLUS D+ Primitive DSUB D- HL ZERO 0 Constant ONE 1 Constant TWO 2 Constant MONE -1 Constant DOCLIT doCLIT Primitive 2012-06-21 SEE SEE extended: handles LIT, CLIT 2012-06-22 SEE SEE extended: handles BRANCH,?BRANCH,?DO,-DO,LOOP,+LOOP,."..." 2012-09-07 SEE SEE ABORT", (DO) added, remarks corrected. TODO: * XXX marks points to open issues. * SEE command: handling of - [COMPILE] - DOCONST, DOVAR, DOUSE TEST: HEX ok 0 8000 8001 U/ . . FFFE 2 ok FFFE 8001 U* . . U* ? ok FFFE 8001 UM* . . 7FFF FFFE ok FFFE 8001 UM* 2 0 D+ . . 8000 0 ok 0 8000 7FFF U/ . . FFFF FFFF ok 0 FFFF FFFF U/ . . FFFF FFFF ok 0 FFFE FFFF U/ . . FFFE FFFE ok FFFF FFFF UM* . . FFFE 1 ok FFFF FFFE FFFF U/ . . FFFF FFFE ok Links/References ================ Project: https://github.com/6809/sbc09 Maintained by the original author and others. Source: http://groups.google.com/group/alt.sources/browse_thread/thread/8bfd60536ec34387/94a7cce3fdc5df67 Autor: Lennart Benschop lennart@blade.stack.urc.tue.nl, lennartb@xs4all.nl (Webpage, Subject must start with "Your Homepage"!) Newsgroups: alt.sources From: lennart@blade.stack.urc.tue.nl (Lennart Benschop) Date: 3 Nov 1993 15:21:16 GMT Local: Mi 3 Nov. 1993 17:21 Subject: 6809 assembler and simulator (examples) 2/2 Homepage/Download links of Lennart Benschop: http://lennartb.home.xs4all.nl/m6809.html http://lennartb.home.xs4all.nl/sbc09.tar.gz http://lennartb.home.xs4all.nl/A09.c Emulator for 6809 written in Python, can run sbc09 ROM: https://github.com/jedie/DragonPy/ Newer posting in alt.sources (1994): Newsgroups: alt.sources From: lenn...@blade.stack.urc.tue.nl (Lennart Benschop) Date: 17 May 1994 08:13:25 GMT Local: Di 17 Mai 1994 10:13 Subject: 6809 assembler/simulator (3 of 3) Referenced by: http://foldoc.org/6809 Reference points to posting with buggy version from 1993. http://lennartb.home.xs4all.nl/m6809.html BAD LINK: http://www.sandelman.ocunix.on.ca/People/Alan_DeKok/interests/6809.html -> http://www.sandelman.ottawa.on.ca/People/Alan_DeKok/interests/ 6809 specific site will be redirected, but does not exist. Internet-Archiv: https://web.archive.org/web/20070112041235/http://www.striker.ottawa.on.ca/6809/ 2014-05-01: Lennart B. lennartb@xs4all.nl has been informed. http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=5&t=4308&start=60#p9750