To: Users From: Peter Schorn Subj: AltairZ80 Simulator Usage Date: 05-Apr-2005 COPYRIGHT NOTICE The following copyright notice applies to both the SIMH source and binary: Copyright (c) 2002-2005, Peter Schorn Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL PETER SCHORN BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Except as contained in this notice, the name of Peter Schorn shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from Peter Schorn. Based on work by Charles E Owen (c) 1997 This memorandum documents the Altair 8800 Simulator with Z80 support. 1. Simulator Files sim/scp.h sim_console.h sim_defs.h sim_fio.h sim_rev.h sim_sock.h sim_timer.h sim_tmxr.h scp.c sim_console.c sim_fio.c sim_sock.c sim_timer.c sim_tmxr.c sim/AltairZ80/altairz80_defs.h altairz80_cpu.c altairz80_dsk.c altairz80_hdsk.c altairz80_sio.c altairz80_sys.c 2. Revision History - 05-Apr-2005, removed bogus t-state stepping support - 24-Jul-2004, Peter Schorn (updated CP/M 2 and SPL packages) - 12-Apr-2004, Peter Schorn (added MAP/NOMAP capability to switch off key mapping) - 26-Jan-2004, Peter Schorn (added support for t-state stepping) - 25-Feb-2003, Peter Schorn (added support for real time simulation) - 9-Oct-2002, Peter Schorn (added support for simulated hard disk) - 28-Sep-2002, Peter Schorn (number of tracks per disk can be configured) - 19-Sep-2002, Peter Schorn (added WARNROM feature) - 31-Aug-2002, Peter Schorn (added extended ROM features suggested by Scott LaBombard) - 4-May-2002, Peter Schorn (added description of MP/M II sample software) - 28-Apr-2002, Peter Schorn (added periodic timer interrupts and three additional consoles) - 15-Apr-2002, Peter Schorn (added memory breakpoint) - 7-Apr-2002, Peter Schorn (added ROM / NOROM switch) Original version of this document written by Charles E Owen 3. Background. The MITS (Micro Instrumentation and Telemetry Systems) Altair 8800 was announced on the January 1975 cover of Popular Electronics, which boasted you could buy and build this powerful computer kit for only $397. The kit consisted at that time of only the parts to build a case, power supply, card cage (18 slots), CPU card, and memory card with 256 *bytes* of memory. Still, thousands were ordered within the first few months after the announcement, starting the personal computer revolution as we know it today. Many laugh at the small size of the that first kit, noting there were no peripherals and the 256 byte memory size. But the computer was an open system, and by 1977 MITS and many other small startups had added many expansion cards to make the Altair quite a respectable little computer. The "Altair Bus" that made this possible was soon called the S-100 Bus, later adopted as an industry standard, and eventually became the IEE-696 Bus. 4. Hardware We are simulating a fairly "loaded" Altair 8800 from about 1977, with the following configuration: device simulates name(s) CPU Altair 8800 with Intel 8080 CPU board, 62KB of RAM, 2K of EPROM with start boot ROM. SIO MITS 88-2SIO Dual Serial Interface Board. Port 1 is assumed to be connected to a serial "glass TTY" that is your terminal running the Simulator. PTR Paper Tape Reader attached to port 2 of the 2SIO board. PTP Paper Tape Punch attached to port 2 of the 2SIO board. This also doubles as a printer port. DSK MITS 88-DISK Floppy Disk controller with up to eight drives. 4.1 CPU We have 2 CPU options that were not present on the original machine but are useful in the simulator. We also allow you to select memory sizes, but be aware that some sample software requires the full 64K (i.e. CP/M) and the MITS Disk Basic and Altair DOS require about a minimum of 24K. SET CPU 8080 Simulates the 8080 CPU (normal) SET CPU Z80 Simulates the Z80 CPU. Note that some software (e.g. most original Altair software such as 4K Basic) requires an 8080 CPU and will not or not properly run on a Z80. This is mainly due to the use of the parity flag on the 8080 which has not always the same semantics on the Z80. SET CPU ITRAP Causes the simulator to halt if an invalid opcode is detected (depending on the chosen CPU). SET CPU NOITRAP Does not stop on an invalid Opcode. This is how the real 8080 works. Note that some software such as 4K Basic apparently tries to execute nonexistent 8080 instructions. Therefore it is advisable in this case to SET CPU NOITRAP. SET CPU 4K SET CPU 8K SET CPU 12K SET CPU 16K ...... (in 4K steps) SET CPU 64K All these set various CPU memory configurations. SET CPU BANKED Enables the banked memory support. The simulated memory has eight banks with address range 0..'common' (see registers below) and a common area from 'common' to 0xfff which is common to all banks. The currently active bank is determined by register 'bank' (see below). You can only switch to banked memory if the memory is set to 64K. The banked memory is used by CP/M 3. SET CPU NONBANKED Disables banked memory support. SET CPU ROM Enables the ROM from address 'ROMLOW' to 'ROMHIGH' (see below under CPU Registers) and prevents write access to these locations. This is the default setting. SET CPU NOROM Disables the ROM. SET CPU ALTAIRROM Enables the slightly modified but downwards compatible Altair boot ROM at addresses 0FF00 to 0FFFF. This is the default. SET CPU NOALTAIRROM Disables standard Altair ROM behavior. SET CPU WARNROM Enables warning messages to be printed when the CPU attempts to write into ROM or into non-existing memory. Also prints a warning message if the CPU attempts to read from non-existing memory. SET CPU NOWARNROM Suppresses all warning message of "WARNROM". Note that some software tries on purpose to write to ROM in order to detect the available RAM. The BOOT EPROM card starts at address 0FF00 if it has been enabled by 'SET CPU ALTAIRROM'. Jumping to this address will boot drive 0 of the floppy controller (CPU must be set to ROM or equivalent code must be present). If no valid bootable software is present there the machine crashes. This is historically accurate behavior. The real 8080, on receiving a HLT (Halt) instruction, freezes the processor and only an interrupt or CPU hardware reset will restore it. The simulator is a lot nicer, it will halt but send you back to the simulator command line. CPU Registers include the following: Name Size Comment PC 16 The Program Counter AF 16 The accumulator and the flag register F = S Z - AC - P/V N C S = Sign flag. Z = Zero Flag. AC = Auxiliary Carry flag. P/V = Parity flag on 8080 Parity / Overflow flag on Z80 - = not used (undefined) N = Internal sign flag C = Carry flag. BC 16 The BC register pair. Register B is the high 8 bits, C is the lower 8 bits DE 16 The DE register pair. Register D is the high 8 bits, E is the lower 8 bits. HL 16 The HL register pair. Register H is the high 8 bits, L is the lower 8 bits. AF1 16 The alternate AF register (on Z80 only) BC1 16 The alternate BC register (on Z80 only) DE1 16 The alternate DE register (on Z80 only) HL1 16 The alternate HL register (on Z80 only) IX 16 The IX index register (on Z80 only) IY 16 The IY index register (on Z80 only) IFF 8 Interrupt flag (on Z80 only) INT 8 Interrupt register (on Z80 only) SR 16 The front panel switches (use D SR 8 for 4k Basic). WRU 8 The interrupt character. This starts as 5 (ctrl-E) but some Altair software uses this keystroke so best to change this to something exotic such as 035 (which is Ctl-]). BANK 3 The currently active memory bank (if banked memory is activated - see memory options above) COMMON 16 The starting address of common memory. Originally set to 0xc000 (note this setting must agree with the value supplied to GENCPM for CP/M 3 system generation) ROMLOW 16 The starting address of the ROM. Default is 0FF00. ROMHIGH 16 The final address of the ROM. Default is 0FFFF. CLOCK 32 The clock speed of the simulated CPU in kHz or 0 to run at maximum speed. To set the clock speed for a typical 4 MHz Z80 CPU, use D CLOCK 4000. The CP/M utility SPEED measures the clock speed of the simulated CPU. 4.2 The Serial I/O Card (2SIO) This simple programmed I/O device provides 2 serial ports to the outside world, which could be hardware jumpered to support RS-232 plugs or a TTY current loop interface. The standard I/O addresses assigned by MITS was 10-11 (hex) for the first port, and 12-13 (hex) for the second. We follow this standard in the Simulator. The simulator directs I/O to/from the first port to the screen. The second port reads from an attachable "tape reader" file on input, and writes to an attachable "punch file" on output. These files are considered a simple stream of 8-bit bytes. The SIO can be configured in SIMH with the following commands: SET SIO TTY Bit 8 is set to zero on console output SET SIO ANSI Bit 8 is not touched on console output SET SIO ALL Console input remain unchanged SET SIO UPPER Console input is transformed to upper case characters only (This feature is useful for most Altair software) SET SIO MAP must also have been executed for this option to take effect - otherwise no mapping occurs. SET SIO BS Map the delete character to backspace SET SIO MAP must also have been executed for this option to take effect - otherwise no mapping occurs. SET SIO DEL Map the backspace character to delete SET SIO MAP must also have been executed for this option to take effect - otherwise no mapping occurs. SET SIO QUIET Do not print warning messages SET SIO VERBOSE Print warning messages (useful for debugging) The register SIOWL determines how often the same warning is displayed. The default is 3. SET SIO MAP Enable mapping of characters (see also SET SIO ALL/UPPER/BS/DEL) SET SIO NOMAP Disable mapping of characters (see also SET SIO ALL/UPPER/BS/DEL) You can also attach the SIO to a port: ATTACH SIO 23 Console IO goes via a Telnet connection on port 23 DETACH SIO Console IO goes via the regular SIMH console 4.3 The SIMH pseudo device The SIMH pseudo device facilitates the communication between the simulated ALTAIR and the simulator environment. This device defines a number of (most R/O) registers (see source code) which are primarily useful for debugging purposes. The SIMH pseudo device can be configured with SET SIMH QUIET Do not print warning messages SET SIMH VERBOSE Print warning messages (useful for debugging) SET SIMH TIMERON Start periodic timer interrupts SET SIMH TIMEROFF Stop the periodic timer interrupts The following variables determine the behavior of the timer: TIMD This is the delay between consecutive interrupts in milliseconds. Use D TIMD 20 for a 50 Hz clock. TIMH This is the address of the interrupt handler to call for a timer interrupt. 4.4 The 88-DISK controller. The MITS 88-DISK is a simple programmed I/O interface to the MITS 8-inch floppy drive, which was basically a Pertec FD-400 with a power supply and buffer board built-in. The controller supports neither interrupts nor DMA, so floppy access required the sustained attention of the CPU. The standard I/O addresses were 8, 9, and 0A (hex), and we follow the standard. Details on controlling this hardware are in the altairz80_dsk.c source file. The only difference is that the simulated disks may be larger than the original ones: The original disk had 77 tracks while the simulated disks support up to 254 tracks (only relevant for CP/M). You can change the number of tracks per disk by setting the appropriate value in TRACKS[..]. For example "D TRACKS[0] 77" sets the number of tracks for disk 0 to the original number of 77. The command "D TRACKS[0-7] 77" changes the highest track number for all disks to 77. For debugging purposes you can set the trace level of some disk I/O functions. To do so the following bits in TRACE (a register of the disk) have been defined with the following meaning: 1 Trace all IN and OUT instructions on the disk ports 8 and 9 2 Trace all read and writes to full sectors on the disk 4 Print a message whenever an unnecessary step-in or step out of the disk head occurs (often an indication of an infinite loop) 8 Print a message whenever the disk head appears to be waiting for a sector which does not show up (often an indication of an infinite loop) For example the command "D TRACE 10" will trace options 2+8 from above. The DSK device can be configured with SET DSK QUIET Do not print warning messages for disk SET DSK VERBOSE Print warning messages for disk (useful for debugging) The register DSKWL determines how often the same warning is displayed. The default is 3. SET DSK WRITEENABLED Allow write operations for disk SET DSK LOCKED Disk is locked, i.e. no write operations will be allowed. 4.5 The simulated hard disk In order to increase the available storage capacity, the simulator features 8 simulated hard disks with a capacity of 8MB (HDSK0 to HDSK7). Currently only CP/M supports two hard disks as devices I: and J:. For debugging purposes one can set the trace flag by executing the command "D HDTRACE 1". The default for "HDTRACE" is 0 (no trace). The HDSK device can be configured with SET HDSK QUIET Do not print warning messages for hard disk SET HDSK VERBOSE Print warning messages for hard disk (useful for debugging) SET HDSK WRITEENABLED Allow write operations for hard disk SET HDSK LOCKED Hard disk is locked, i.e. no write operations will be allowed. 5. Sample Software Running an Altair in 1977 you would be running either MITS Disk Extended BASIC, or the brand new and sexy CP/M Operating System from Digital Research. Or possibly, you ordered Altair DOS back when it was promised in 1975, and are still waiting for it to be delivered in early 1977. We have samples of all three for you to check out. We can't go into the details of how they work, but we'll give you a few hints. 5.1 CP/M Version 2.2 This version is my own port of the standard CP/M to the Altair. There were some "official" versions but I don't have them. None were endorsed or sold by MITS to my knowledge, however. To boot CP/M: sim> attach dsk cpm2.dsk sim> boot dsk CP/M feels like DOS, sort of. DIR will work. I have included all the standard CP/M utilities, plus a few common public-domain ones. I also include the sources to the customized BIOS and some other small programs. TYPE will print an ASCII file. DUMP will dump a binary one. LS is a better DIR than DIR. ASM will assemble .ASM files to Hex, LOAD will "load" them to binary format (.COM). ED is a simple editor, #A command will bring the source file to the buffer, T command will "type" lines, L will move lines, E exits the editor. 20L20T will move down 20 lines, and type 20. Very DECish. DDT is the debugger, DO is a batch-type command processor. A sample batch file that will assemble and write out the bootable CP/M image (on drive A) is "SYSCPM2.SUB". To run it, type "DO SYSCPM2". In order to efficiently transfer files into the CP/M environment use the included program R . If you have a file named foo.ext in the current directory (i.e. the directory where SIMH is), executing R FOO.EXT under CP/M will transfer the file onto the CP/M disk. Transferring a file from the CP/M environment to the SIMH environment is accomplished by W for text files or by W B for binary files. The simplest way for transferring multiple files is to create a ".SUB" batch file which contains the necessary R resp. W commands. If you need more storage space you can use a simulated hard disk on drives I: and J:. To use do "attach HDSK0 hdi.dsk" and issue the "XFORMAT I:" resp. "XFORMAT J:" command from CP/M do initialize the disk to an empty state. The disk "cpm2.dsk" contains the following files: Name Ext Size Comment ASM .COM 8K ; CP/M assembler BDOS .MAC 68K ; Basic Disk Operating System assembler source code BOOT .COM 1K ; transfer control to boot ROM BOOT .MAC 2K ; source for BOOT.COM BOOTGEN .COM 2K ; put a program on the boot sectors CBIOSX .MAC 48K ; CP/M 2 BIOS source for Altair CCP .MAC 26K ; Console Command Processor assembler source code COPY .COM 2K ; copy disks CPMBOOT .COM 12K ; CP/M operating system CPU .COM 2K ; get and set the CPU type (8080 or Z80) CPU .MAC 2K ; source for CPU.COM CREF80 .COM 4K ; cross reference utility DDT .COM 6K ; 8080 debugger DDTZ .COM 10K ; Z80 debugger DIF .COM 4K ; determine differences between two files DO .COM 2K ; batch processing DSKBOOT .MAC 8K ; source for boot ROM DUMP .COM 2K ; hex dump a file ED .COM 8K ; line editor ELIZA .BAS 10K ; Eliza game in Basic EX8080 .COM 12K ; exercise 8080 instruction set EXZ80DOC.COM 12K ; exercise Z80 instruction set, No undefined status bits EXZ80ALL.COM 12K ; exercise Z80 instruction set, Undefined status bits EX .MAC 54K ; source for EX8080.COM, EXZ80DOC.COM, EXZ80ALL.COM EX .SUB 2K ; benchmark execution of EX8080.COM,EXZ80DOC.COM,EXZ80ALL.COM FORMAT .COM 2K ; format disks GO .COM 0K ; start the currently loaded program at 100H HDSKBOOT.MAC 6K ; boot code for hard disk L80 .COM 12K ; Microsoft linker LADDER .COM 40K ; game LADDER .DAT 2K ; high score file for LADDER.COM LIB80 .COM 6K ; library utility LOAD .COM 2K ; load hex files LS .COM 4K ; directory utility LU .COM 20K ; library utility M80 .COM 20K ; Microsoft macro assembler MBASIC .COM 24K ; Microsoft Basic interpreter MC .SUB 2K ; assemble and link an assembler program MCC .SUB 2K ; read, assemble and link an assembler program MCCL .SUB 2K ; assemble, link and produce listing MEMCFG .LIB 2K ; defines the memory configuration MOVER .MAC 2K ; moves operating system in place OTHELLO .COM 12K ; Othello (Reversi) game PIP .COM 8K ; Peripheral Interchange Program PRELIM .COM 2K ; preliminary CPU tests PRELIM .MAC 6K ; source code for PRELIM.COM R .COM 4K ; read files from SIMH environment RSETSIMH.COM 2K ; reset SIMH interface RSETSIMH.MAC 2K ; assembler source for RSETSIMH.COM SHOWSEC .COM 3K ; show sectors on a disk SID .COM 8K ; debugger for 8080 SPEED .COM 2K ; utility to measure the clock speed of the simulated CPU STAT .COM 6K ; provide information about currently logged disks SURVEY .COM 2K ; system survey SURVEY .MAC 16K ; assembler source for SURVEY.COM SYSCOPY .COM 2K ; copy system tracks between disks SYSCPM2 .SUB 2K ; create CP/M 2 on drive A: TIMER .COM 2K ; perform various timer operations TIMER .MAC 2K ; source code for TIMER.COM UNCR .COM 8K ; un-crunch utility UNERA .COM 2K ; un-erase a file UNERA .MAC 16K ; source for UNERA.COM USQ .COM 2K ; un-squeeze utility W .COM 4K ; write files to SIMH environment WM .COM 12K ; word master screen editor WM .HLP 3K ; help file for WM.COM WORM .COM 4K ; worm game for VT100 terminal XFORMAT .COM 2K ; initialize a drive (floppy or hard disk) XSUB .COM 2K ; support for DO.COM ZAP .COM 10K ; SuperZap 5.2 disk editor configured for VT100 ZSID .COM 10K ; debugger for Z80 ZTRAN4 .COM 4K ; translate 8080 mnemonics into Z80 equivalents 5.2 CP/M Version 3 with banked memory CP/M 3 is the successor to CP/M 2.2. A customized BIOS (BIOS3.MAC) is included to facilitate modification if so desired. The defaults supplied in GENCPM.DAT for system generation can be used. BOOTGEN.COM is used to place the CP/M loader (LDR.COM) on the boot tracks of a disk. Running CP/M 3 with banked memory: sim> attach dsk cpm3.dsk sim> reset cpu sim> set cpu banked sim> set cpu itrap sim> boot dsk Executing "DO SYSCPM3" will re-generate the banked version of CP/M 3. You can boot CP/M 3 with or without a Z80 CPU. The Z80 CPU is needed for both sysgens due to the use of BOOTGEN.COM which requires it. The disk "cpm3.dsk" contains the following files: ASM .COM 8K ; CP/M assembler ASSIGN .SYS 2K BDOS3 .SPR 10K BIOS3 .MAC 28K ; CP/M 3 BIOS source for Altair SIMH BIOS3 .SPR 4K BNKBDOS3.SPR 14K BNKBIOS3.SPR 4K BOOT .COM 2K ; transfer control to boot ROM BOOTGEN .COM 2K ; put a program on the boot sectors CCP .COM 4K COPYSYS .COM 2K CPM3 .SYS 18K CPMLDR .MAC 38K ; CP/M 3 loader assembler source DATE .COM 4K ; date utility DDT .COM 6K ; 8080 debugger DDTZ .COM 10K ; Z80 debugger DEFS .LIB 2K ; include file for BIOS3.MAC to create banked CP/M 3 DEVICE .COM 8K DIF .COM 4K ; determine differences between two files DIR .COM 16K ; directory utility DO .COM 6K ; batch processing DUMP .COM 2K ED .COM 10K ERASE .COM 4K GENCOM .COM 16K GENCPM .COM 22K GENCPM .DAT 4K ; CP/M generation information for banked version GENCPMNB.DAT 4K ; CP/M generation information for non-banked version GET .COM 8K HELP .COM 8K ; help utility HELP .HLP 62K ; help files HEXCOM .CPM 2K HIST .UTL 2K INITDIR .COM 32K L80 .COM 12K ; Microsoft linker LDR .COM 4K ; CP/M loader with optimized loader BIOS LDRBIOS3.MAC 14K ; optimized (for space) loader BIOS LIB .COM 8K ; Digital Research librarian LINK .COM 16K ; Digital Research linker LOAD .COM 2K M80 .COM 20K ; Microsoft macro assembler MC .SUB 2K ; assemble and link an assembler program MCC .SUB 2K ; read, assemble and link an assembler program PATCH .COM 4K PIP .COM 10K ; Peripheral Interchange Program PROFILE .SUB 2K ; commands to be executed at start up PUT .COM 8K R .COM 4K ; read files from SIMH environment RENAME .COM 4K RESBDOS3.SPR 2K RMAC .COM 14K ; Digital Research macro assembler RSETSIMH.COM 2K ; reset SIMH interface SAVE .COM 2K SCB .MAC 2K SET .COM 12K SETDEF .COM 6K SHOW .COM 10K SHOWSEC .COM 4K ; show sectors on a disk SID .COM 8K ; 8080 debugger SYSCOPY .COM 2K ; copy system tracks between disks SYSCPM3 .SUB 2K ; create banked CP/M 3 system TRACE .UTL 2K TSHOW .COM 2K ; show split time TSTART .COM 2K ; create timer and start it TSTOP .COM 2K ; show final time and stop timer TYPE .COM 4K UNERA .COM 2K ; un-erase a file W .COM 4K ; write files to SIMH environment XREF .COM 16K ; cross reference utility ZSID .COM 10K ; Z80 debugger 5.3 MP/M II with banked memory MP/M II is an acronym for MultiProgramming Monitor Control Program for Microprocessors. It is a multiuser operating system for an eight bit microcomputer. MP/M II supports multiprogramming at each terminal. This version supports four terminals available via Telnet. To boot: sim> attach dsk mpm.dsk sim> set cpu itrap sim> set cpu z80 sim> set cpu rom sim> set cpu banked sim> attach sio 23 sim> d common b000 sim> boot dsk Now connect a Telnet session to the simulator and type "MPM" at the "A>" prompt. Now you can connect up to three additional terminals via Telnet to the Altair running MP/M II. To re-generate the system perform "DO SYSMPM" in the CP/M environment (not possible under MP/M since XSUB is needed). The disk "mpm.dsk" contains the following files: Name Ext Size Comment ABORT .PRL 2K ; abort a process ABORT .RSP 2K ASM .PRL 10K ; MP/M assembler BNKBDOS .SPR 12K ; banked BDOS BNKXDOS .SPR 2K ; banked XDOS BNKXIOS .SPR 4K ; banked XIOS BOOTGEN .COM 2K ; copy an executable to the boot section CONSOLE .PRL 2K ; print console number CPM .COM 2K ; return to CP/M CPM .MAC 2K ; source for CPM.COM DDT .COM 6K ; MP/M DDT DDT2 .COM 6K ; CP/M DDT DDTZ .COM 10K ; CP/M DDT with Z80 support DIF .COM 4K ; difference between two files DIR .PRL 2K ; directory command DO .COM 2K ; CP/M submit DSKRESET.PRL 2K ; disk reset command DUMP .MAC 6K ; source for DUMP.PRL DUMP .PRL 2K ; dump command ED .PRL 10K ; MP/M line editor ERA .PRL 2K ; erase command ERAQ .PRL 4K ; erase command (verbose) GENHEX .COM 2K GENMOD .COM 2K GENSYS .COM 10K L80 .COM 12K ; Microsoft linker LDRBIOS .MAC 14K ; loader BIOS LIB .COM 8K ; library utility LINK .COM 16K ; linker LOAD .COM 2K ; loader M80 .COM 20K ; Microsoft macro assembler MC .SUB 2K ; assemble and link an assembler program MCC .SUB 2K ; read, assemble and link an assembler program MPM .COM 8K ; start MP/M II MPM .SYS 26K ; MP/M system file MPMD .LIB 2K ; define a banked system MPMLDR .COM 6K ; MP/M loader without LDRBIOS MPMSTAT .BRS 6K ; status of MP/M system MPMSTAT .PRL 6K MPMSTAT .RSP 2K MPMXIOS .MAC 26K ; XIOS for MP/M PIP .PRL 10K ; MP/M peripheral interchange program PIP2 .COM 8K ; CP/M peripheral interchange program PRINTER .PRL 2K PRLCOM .PRL 4K R .COM 4K ; read a file from the SIMH environment RDT .PRL 8K ; debugger for page relocatable programs REN .PRL 4K ; rename a file RESBDOS .SPR 4K ; non-banked BDOS RMAC .COM 14K ; Digital Research macro assembler RSETSIMH.COM 2K ; reset SIMH interface SCHED .BRS 2K ; schedule a job SCHED .PRL 4K SCHED .RSP 2K SDIR .PRL 18K ; fancy directory command SET .PRL 8K ; set parameters SHOW .PRL 8K ; show status of disks SPOOL .BRS 4K ; spool utility SPOOL .PRL 4K SPOOL .RSP 2K STAT .COM 6K ; CP/M stat command STAT .PRL 10K ; MP/M stat command STOPSPLR.PRL 2K ; stop spooler SUBMIT .PRL 6K ; MP/M submit SYSCOPY .COM 2K ; copy system tracks SYSMPM .SUB 2K ; do a system generation SYSTEM .DAT 2K ; default values for system generation TMP .SPR 2K TOD .PRL 4K ; time of day TSHOW .COM 2K ; show split time TSTART .COM 2K ; create timer and start it TSTOP .COM 2K ; show final time and stop timer TYPE .PRL 2K ; type a file on the screen USER .PRL 2K ; set user area W .COM 4K ; write a file to SIMH environment XDOS .SPR 10K ; XDOS XREF .COM 16K ; cross reference utility XSUB .COM 2K ; for CP/M DO 5.4 CP/M application software There is also a small collection of sample application software containing the following items: - SPL: a Small Programming Language with a suite of sample programs - PROLOGZ: a Prolog interpreter written in SPL with sources - PASCFORM: a Pascal pretty printer written in Pascal - Pascal MT+: Pascal language system needed to compile PASCFORM The sample software comes on "app.dsk" and to use it do sim> attach dsk1 app.dsk before booting CP/M. The disk "app.dsk" contains the following files: Name Ext Size Comment ACKER .SPL 4K ; compute the Ackermann function ACKER .COM 2K ; compute the Ackermann function, SPL source BOOTGEN .COM 2K BOOTGEN .SPL 6K ; SPL source for BOOTGEN.COM C .SUB 2K ; batch file for compiling an SPL source file CALC .PRO 4K ; Prolog demo program: Calculator DIF .COM 4K DIF .SPL 10K ; SPL source for DIF.COM FAC .COM 4K ; compute the factorial FAC .SPL 4K ; compute the factorial, SPL source FAMILY .PRO 4K ; Prolog demo program: Family relations FORMEL .COM 4K ; calculator FORMEL .SPL 6K ; calculator, SPL source INTEGER .PRO 2K ; Prolog demo program: Integer arithmetic KNAKE .PRO 2K ; Prolog demo program: Logic puzzle LINKMT .COM 12K ; Pascal MT+ 5.5 linker MOVE .MAC 4K ; helper functions for PROLOGZ in assembler MTERRS .TXT 6K ; Pascal MT+ error messages MTPLUS .000 14K ; Pascal MT+ 5.5 compiler file MTPLUS .001 12K ; Pascal MT+ 5.5 compiler file MTPLUS .002 8K ; Pascal MT+ 5.5 compiler file MTPLUS .003 8K ; Pascal MT+ 5.5 compiler file MTPLUS .004 18K ; Pascal MT+ 5.5 compiler file MTPLUS .005 8K ; Pascal MT+ 5.5 compiler file MTPLUS .006 6K ; Pascal MT+ 5.5 compiler file MTPLUS .COM 36K ; Pascal MT+ 5.5 compiler PASCFORM.COM 36K ; Pascal formatter PASCFORM.PAS 54K ; Pascal formatter source code PASCFORM.SUB 2K ; create Pascal formatter PASLIB .ERL 24K ; Pascal MT+ 5.5 run time library PINST .COM 4K ; terminal installation program for PROLOGZ PINST .SPL 16K ; terminal installation program for PROLOGZ, SPL source PRIM .COM 2K ; compute prime numbers PRIM .SPL 2K ; compute prime numbers, SPL source PROLOGZ .COM 18K ; PROLOGZ interpreter and screen editor PROLOGZ .SPL 2K ; SPL source for PROLOGZ PROLOGZ .TXT 40K ; PROLOGZ documentation in German QUEEN .PRO 2K ; Prolog demo program: N-queens problem READ .COM 4K READ .SPL 10K ; SPL source for R.COM RELDUMP .COM 4K ; dump a .REL file to the console RELDUMP .SPL 10K ; dump a .REL file to the console, SPL source SHOWSEC .COM 2K SHOWSEC .SPL 6K ; SPL source for SHOWSEC.COM SIEVE .COM 2K ; compute prime numbers with a sieve SIEVE .SPL 6K ; compute prime numbers with a sieve, SPL source SPEED .COM 2K ; utility to measure the clock speed of the simulated CPU SPEED .SPL 4K ; SPL source for SPEED.COM SPL .COM 28K ; the SPL compiler itself SPL .TXT 50K ; SPL language and compiler documentation SPLERROR.DAT 8K ; error messages of the compiler SPLRTLB .REL 2K ; SPL runtime library SYSCOPY .COM 2K SYSCOPY .SPL 6K ; SPL source for SYSCOPY.COM WC .COM 6K ; word count and query facility WC .SPL 14K ; word count and query facility, SPL source WRITE .COM 4K WRITE .SPL 8K ; SPL source for W.COM XFORMAT .COM 2K XFORMAT .SPL 6K ; SPL source for XFORMAT.COM 5.5 MITS Disk Extended BASIC Version 4.1 This was the commonly used software for serious users of the Altair computer. It is a powerful (but slow) BASIC with some extended commands to allow it to access and manage the disk. There was no operating system it ran under. To boot: sim> set cpu 8080 ;Z80 will not work sim> attach dsk mbasic.dsk sim> set sio upper sim> go ff00 MEMORY SIZE? [return] LINEPRINTER? [C return] HIGHEST DISK NUMBER? [0 return] (0 here = 1 drive system) NUMBER OF FILES? [3 return] NUMBER OF RANDOM FILES? [2 return] 44041 BYTES FREE ALTAIR BASIC REV. 4.1 [DISK EXTENDED VERSION] COPYRIGHT 1977 BY MITS INC. OK [MOUNT 0] OK [FILES] 5.6 Altair DOS Version 1.0 This was long promised but not delivered until it was almost irrelevant. A short attempted tour will reveal it to be a dog, far inferior to CP/M. To boot: sim> d tracks[0-7] 77 ;set to Altair settings sim> set cpu altairrom sim> attach dsk altdos.dsk sim> set sio upper sim> go ff00 MEMORY SIZE? [return] INTERRUPTS? N [return] HIGHEST DISK NUMBER? [0 return] (3 here = 4 drive system) HOW MANY DISK FILES? [3 return] HOW MANY RANDOM FILES? [2 return] 056449 BYTES AVAILABLE DOS MONITOR VER 1.0 COPYRIGHT 1977 BY MITS INC .[MNT 0] .[DIR 0] 5.7 Altair Basic 3.2 (4k) In order to run the famous 4k Basic, use the following commands (the trick is to get the Switch Register right). sim> set cpu 8080 ;note 4k Basic will not run on a Z80 CPU sim> set sio upper ;4k Basic does not like lower case letters as input sim> set cpu noitrap ;4k Basic likes to execute non 8080 instructions-ignore sim> set sio ansi ;4k Basic produces 8-bit output, strip to seven bits sim> d sr 8 ;good setting for the Switch Register sim> load 4kbas.bin 0 ;load it at 0 sim> go 0 ;and start it MEMORY SIZE? [return] TERMINAL WIDTH? [return] WANT SIN? [Y] 61911 BYTES FREE BASIC VERSION 3.2 [4K VERSION] OK 5.8 Altair 8k Basic Running 8k Basic follows the procedure for 4k Basic. sim> set cpu 8080 ;note 8k Basic will not run on a Z80 CPU sim> set sio upper ;8k Basic does not like lower case letters as input sim> set sio ansi ;8k Basic produces 8-bit output, strip to seven bits sim> d sr 8 ;good setting for the Switch Register sim> load 8kbas.bin 0 ;load it at 0 sim> go 0 ;and start it MEMORY SIZE? [A] WRITTEN FOR ROYALTIES BY MICRO-SOFT MEMORY SIZE? [return] TERMINAL WIDTH? [return] WANT SIN-COS-TAN-ATN? [Y] 58756 BYTES FREE ALTAIR BASIC REV. 4.0 [EIGHT-K VERSION] COPYRIGHT 1976 BY MITS INC. OK 5.9 Altair Basic 4.0 Execute the following commands to run Altair Extended Basic: sim> set sio upper ;Extended Basic requires upper case input sim> set sio ansi ;Extended Basic produces 8-bit output, strip to 7 bits sim> d sr 8 ;good setting for the Switch Register sim> load exbas.bin 0 ;load it at 0 sim> go 0 ;and start it 16384 Bytes loaded at 0. MEMORY SIZE? [return] WANT SIN-COS-TAN-ATN? [Y] 50606 BYTES FREE ALTAIR BASIC REV. 4.0 [EXTENDED VERSION] COPYRIGHT 1977 BY MITS INC. OK 5.10 Altair Disk Extended Basic Version 300-5-C This version of Basic was provided by Scott LaBombard. To execute use the following commands: sim> d tracks[0-7] 77 ;set to Altair settings sim> at dsk extbas5.dsk sim> g 0 MEMORY SIZE? [return] LINEPRINTER? [C] HIGHEST DISK NUMBER? [0] HOW MANY FILES? [3] HOW MANY RANDOM FILES? [3] 42082 BYTES FREE ALTAIR DISK EXTENDED BASIC VERSION 300-5-C [01NOV78] COPYRIGHT 1978 BY MITS INC. OK 6. Special simulator feature: Memory access breakpoints In addition to the regular SIMH features such as PC queue, breakpoints etc., this simulator supports memory access breakpoints. A memory access breakpoint is triggered when a pre-defined memory location is accessed (read, write or update). To set a memory location breakpoint enter sim> break -m Execution will stop whenever an operation accesses . Note that a memory access breakpoint is not triggered by fetching code from memory (this is the job of regular breakpoints). This feature has been implemented by using the typing facility of the SIMH breakpoints. 7. Brief summary of all major changes to the original Altair simulator - Full support for Z80. CP/M software requiring a Z80 CPU now runs properly. DDTZ and PROLOGZ are included for demonstration purposes. - Added banked memory support. - PC queue implemented. - Full assembler and dis-assembler support for Z80 and 8080 mnemonics. Depending on the current setting of the CPU, the appropriate mnemonics are used. - The BOOT ROM was changed to fully load the software from disk. The original code basically loaded a copy of itself from the disk and executed it. - ROM and memory size settings are now fully honored. This means that you cannot write into the ROM or outside the defined RAM (e.g. when the RAM size was truncated with the SET CPU commands). This feature allows programs which check for the size of available RAM to run properly (e.g. 4k Basic). In addition one can enable and disable the ROM which is useful in special cases (e.g. when testing a new version of the ROM). - The console can also be used via Telnet. This is useful when a terminal is needed which supports cursor control such as a VT100. PROLOGZ for example has a built-in screen editor which works under Telnet. - Simplified file exchange for CP/M. Using the READ program under CP/M one can easily import files into CP/M from the regular file system. Note that PIP does not work properly on non-text files on PTR. - The WRITE program can be used to transfer files from the CP/M environment to the regular environment (binary or ASCII transfer). - The last character read from PTR is always Control-Z (the EOF character for CP/M). This makes sure that PIP (Peripheral Interchange Program on CP/M) will terminate properly. - Fixed a bug in the BIOS warm boot routine which caused CP/M to crash. - Modified the BIOS for CP/M to support 8 disks. - Added CP/M 3 banked version as sample software - Changed from octal to hex - Made the DSK and SIO device more robust (previously malicious code could crash the simulator) - Added memory access break points - Added periodic timer interrupts (useful for MP/M) - Added additional consoles (useful for MP/M) - Added MP/M II banked version as sample software