PN 81-260
A larger 6502 SBC, 2 VIA 6522, 2K RAM, RK ROM
Category Archives: 6502
John Bell PN 80-153
PN 80-153
Five IC’s on a SBC: 6502, 6522 VIA, 2716 EPROM, 2x 2114 SRAM, 74LS10 decoder
PCB images by Glen Deas, thanks!
(Clock modification with crystal, Don Sawyer)
This is a revision, connecting phi2 to pin 11 of the ‘LS10, “to improve memory response”, so the wire is soldered!
See also:
Elektor Junior ASSM/TED
KIM-1 Macro Assembler Editor
MAE ASSM/TED CW Moser
SYM-1 RAE
My retro toolchain
Development for my old 8 bit retro SBC’s has become much easier with fast PCs and good tools. All cross development.
What took hours on my KIM-1: load editor form tape -edit source – save on tape (multiple tape files if big) – assemble form tape to tape – load binary from tape – run
can now be done very fast.
Powerful text editors, cross assembler, KIM-1 Simulator, seconds per iteration.
The only slow part remains: me!
More on my favorite toolchain here.
See also:
Focal-65 V3D for TIM and KIM-1
John Bell Engineering catalogs
New KIM-1 info and more
KIM-1 Simulator simple demo
PC Tools
Updated December 2020, Linux compilation checked, bugs fixed, online program for comverting binary to wave file.
To aid in the handling of KIM-1 program and dataformats I have written some programs for Windows and Linux (Raspbian), sources included.
KIM-1 simulator
Convert 8 bit hex formats
KIMPaper
KIM Tape WAV to BIN conversion
KIMPoser Tape Convert hex to WAV online
KIM Tape Convert WAV to BIN and BIN to WAV
Pascal-M cross compiler
All programs come with source (Free Pascal Lazarus), compiled for Windows but thanks to Freepascal and Lazarus also compiled and tested on Linux (Ubuntu and Raspberry PI OS).
Convert 8 bit hex formats
A general purpose utility to convert common 8 bit hex and binary formats, such as Intel HEX, Motorola S records, MOS Papertape, hex format, and binary files.
Sources (Freepascal Lazarus).
Convert8bithexformat Setup for Windows, Executables for Ubuntu and Raspberry PI OS
Available formats:
– BIN binary, raw data, no formatting, no information on start address.
– HEX formatted as hex numbers raw data, no start address included.
– IHEX Intel hex 8 bit format, multiple memory block, start address included.
– PAP MOS Technology papertape format, multiple memory blocks, start address included.
– SREC Motorola 8 bit S record, contiguous memory block, start address included.
– A1hex Apple Woz monitor hex format, start address included.
– KIM Tape as used in the KIM-1 Simulator as emulation of audio tape files.
KIM-1 simulator
6502/65C02 CPU emulation, disassembler, TTY, KIM-1 keypad and LEDs.
See the KIM-1 Simulator page for more information.
KIM Paper
Note that the Conver8bitHexFormat program is also capable of converting to and from Papertape format from many more formats.
Originally written for the launch of the MicroKIM, an older version is on the support CD.
When you attach a serial device like the teletype or a modern PC with Hyperterminal you can use the TIM monitor of the KIM-1. One of the functions is loading from and saving to a papertape device on the teletype. Now since this is a way to load and save data as a textfile this is in fact quite useful.
The Micro-KIM triggered me to modernize my conversion utility for MOS Technology papertape format dating from 1983, VAX/VMS and Turbo Pascal. A Windows and a commandline/console version are available.
KIMPAPER for Windows
A program for Windows to convert between papertape and binary format.
Windows setup KIMPAPER
Sources (Freepascal Lazarus, build also on Linux)
KIMPAPER V1.1 for DOS
Not too modern, but handy, a commandline utility. Does exactly the same as the Windows program KIMPAPER. Runs fine in a commandline DOS box. Can also be compiled for Linux with Freepascal. In the KIMPAPER DOS archive the program, source and information on the program and papertape format can be found.
C:\MICROKIM\kimpaper KIM-1 MOS Technology BIN papertape format conversion utility, Hans Otten, 2007 v1.1 Syntax is: KIMPAPER [-[b|p] filename [startaddress] C:\MICROKIM\kimpaper -h KIM-1 Mos Technology BIN papertape format conversion utility, Hans Otten, 2007 v1.1 Syntax is: KIMPAPER [-[b|p|h] filename [startaddress] first parameter switches -h help -p convert to papertape -b convert to binary second parameter (first if no parameters, assumed binary to papertape) name of file to convert .BIN for binary, forces conversion to PAPertape .PAP for papertape, forces conversion to BINary third parameter (assumed 0000 if not present) startaddress for BIN to papertape conversion Files of type .BIN wil force conversion to papertape.PAP Files of type .PAP wil force conversion to binary .BIN Examples: C:\MICROKIM\kimpaper mastermind.bin 0200 KIM-1 Mos Technology BIN papertape format conversion utility, Hans Otten, 2007 v1.1 C:\MICROKIM>kimpaper mastermind.pap KIM-1 Mos Technology BIN papertape format conversion utility, Hans Otten, 2007 v1.1 Start address 0200 in file mastermind.BIN
Convert KIM tape to text
KIM Tape to Text is a utility to convert between binary format of a KIM-1 tape dump to a DOS text file.
The KIM tape dump is a binary file and is just a dump of part of the memory of the KIM-1.
This binary file can be a text file as used in editors Micro Ade or CW Assm/TED.
By using the tape write routine in the KIM-1 one can write an audio file on cassette.
When this audio file is captured on a PC as WAV file (22K, mono) this can be converted back to a binary memory dump with ED’s Utility KIMTape
These text files can be converted to DOS text files with this utility.
First open the binary file. If this is recognized as Micro Ade or CW Moser format, the Save as text file can be used.
Windows program.
Full source for Freepascal and Lazarus, no Windows dependencies. Compiled on 64 bits Windows 10 as 32 bit application.
Note on detection of assembler editor type
1. Micro Ade file must start with CR: when present this is Micro Ade
line nr follows 2 byte
line ends with $0D
file ends with $40
2. Assm/Ted by CW Moser starts with line number $10 $00
end of line is high bit set
There may be rare situations that a file starts with a $0D or a different line nr. You can force CW Mose detection by changing this to a sequence of $10 $00 $0D and if necessary blanks $20 to make it consistent. If in doubts: use an editor that shows the file in hex (Ultra Edit, or the free Notepad ++, Text editor PRO) and study the tape file.
Methods to get the binary file out of a Junior or KIM-1.
Read the record tape into a binary with Ed’s KIMTAPE conversion *see below). It is MS-DOS and runs fine in VDOS (https://www.vdos.info/) or DOsbox (slow).
Make a note of start address as shown by KIMTAPE.
Non-printing ASCII characters are filtered out of the resulting text file.
KIM Tape Convert WAV to BIN and BIN to WAV
Not my program, but so handy!
KIMTAPE v0.5 – tape conversion utility for KIM-1 and SYM-1 (2004-05-17) Local copy of http://dxforth.mirrors.minimaltype.com/#kimtape)
KIMTAPE allows programs stored on cassette tape to be decoded to a program file. It handles both MOS Technology KIM-1 and Synertek SYM-1 tape formats including HYPERTAPE. The reverse process – converting a program file to an audio wavefile is also possible, allowing one to produce perfectly regenerated cassettes. KIMTAPE works with 8-bit mono WAV, VOC or RAW audio files recorded
at 22050 samples per second.
Download: kimtap05.zip (MS-DOS) It is MS-DOS and runs fine in VDOS (https://www.vdos.info/) or DOSbox (slow).
The binary files in the KIM-1 program archives have been reproduced, from the original cassette recordings, with the tool KIMTAPE on a PC in a DOS box. See Eds DX-Forth and Utilities Page for this and other nice programs.
This program also makes it possible to reproduce the original cassette recordings that can be read by a KIM-1.
The files were made as follows: The KIM-1 cassette audio was connected to the PC audio input and (with e.g. Audacity) recorded as a wave file (mono 22KHz).
For example: qchess.wav
The wave file was then converted with KIMTAPE to a binary file (the exact content of of the KIM-1 memory when recorded).
And the KIMTAPE utility then displays load address (for example and tape ID
c:\kimtape qchess.wav qchess.bin KIMTAPE version 0.5 17-May-04 infile: qchess.wav outfile: qchess.BIN Program 01 address 0200 checksum OK xxxx bytes done
This .bin file (any extension is fine!) is NOT a wave file! It contains the exact content of the KIM-1 memory when recorded. The size is exactly the number of bytes as stored in the memory of the KIM-1 and much smaller than the wave file. This binary file can be converted back to a wave file with KIMTAPE or converted to a papertape file with KIMPAPER:
C:\kimtape -M -A0200 -D01 -B2 qchess.bin qchess.wav
As you can see: you have to specify the load address and the program ID. The B parameter indicates hypertape speed (2 here, slow)
The resulting wav file should be acceptable for the KIM-1. It is (as I have tested) acceptable as input for KIMTAPE!
All command parameters can be seen by typing KIMTAPE without parameters:
Pascal-M Cross compiler
Executables of cross compiler, workflow, sources, command line utilities.
See also:
Elektor Junior ASSM/TED
KIM-1 Macro Assembler Editor
MAE ASSM/TED CW Moser
SYM-1 RAE
My retro toolchain
About my toolchains for retro computing.
Tools are very personal choice, what works for me. I use Windows (11 now) as my main workstation and often the command line. I do have Linux desktops for compatibility testing. As I grew up in the 80ties with mini’s like HP1000, PDP-11 + RSX-11M, VAX/VMS, MS-DOS, all command line, many many editors, from line editors to screen oriented (EDT from DEC was great!) with all kind of automation tools and code management, I feel comfortable with what Windows (and Linux) offer me now, it makes me very productive! YMMV, pick your tools as you like it.
Tools development
When there is not a tool available that does easy what I need, I write my own. GUI or command line, depending on the context.
My toolchain consists of Freepascal (commandline) and Lazarus (GUI).
Most tools have to do with manipulating binary data as to be expected. Other areas are compilers and simulators.
Resulting tools run on Windows, Linux and Apple Mac’s. See the
Assembly toolchain
I have quite a collection of 8 bit computers, 6502, Z80, 6809.
Each processor comes with its own machine language, and for each processor myriads of assemblers have been made, each with its own deviations of the official syntax and way they operate. The simple ones are two-pass assemblers generating binaries and listings and symbol tables. More advanced are made up of an assembler and a linker. Linkers are nice and powerful, but a bit overkill for simple projects. I like command line assemblers, callable from an editor.
Notepad++ Editor
A very powerful text editor, with syntax highlighting, multiple files windows open, good search, plugins like hex editor and external tools support.
- Install latest version from the download
- Add plugins Hexeditor and NPPEXEC
- make6502pap tasm -65 -x3 -g1 -s “$(FILE_NAME)” “$(NAME_PART).pap” “$(NAME_PART).lst” -s “$(NAME_PART).sym”
- make6502bin tasm -65 -g3 -s -l -fff “$(FILE_NAME)” “$(NAME_PART).bin” “$(NAME_PART).lst” -s “$(NAME_PART).sym”
- make6502hex tasm -65 -x3 -g0 -s “$(FILE_NAME)” “$(NAME_PART).ihex” “$(NAME_PART).lst” -s “$(NAME_PART).sym”
- makez80hex tasm -80 -g0 -s “$(FILE_NAME)” “$(NAME_PART).ihex” “$(NAME_PART).lst” -s “$(NAME_PART).sym”
- etc, see c:\tasm\TASMMAN,HTM
- Edit you source
- Assembly first time: press F6 choose wanted script
- After that Press CTRL-F6 to asemble
- The output of the assemble appears at the bottom of the editor in a separate part
- Open in Notepad also the listing file
- If errors, correct the source
- if errorfree, start debugging your code, leave Notepad++ open to edit source and read the listing
Add scripts to nppexec such as (requires TASM 2 installed, read below)
TASM32
This is a command line assembler that supports processors like 6502 and Z80. Output is binary, MOS papertape, Intel Hex, Motorola S-record. Listings and symbol tables (for the KIM-1 Simulator) can be generated. Used from Notepad++ as Tool, no need to start from the command line.
- Download TASM 32 here
- Unpack in e.g. c:\tasm
- Create environment variable TASMTABS=C:\TASM
(Settings – Related Settings – Advanced system settings – Advanced tab – Environment Variables). - Add c:\tasm to the PATH
- Invoke tasm from the command line without arguments for help and/or read TASMMAN.HTM in C:/tasm
- Add macro’s to Notepad++, see there.
Test and debug
The output of the assembler can be downloaded to the SBC. Burn an EPROM, download hex or papertape. And test the code.
For KIM-1 programs I always use the KIM-1 Simulator debugger on the PC.
Set breakpoints and watches, trace the code, inspect memory, run the program.
When it is a TTY console program, I sue a terminal emulator, Teraterm.
2400 baud 8 bit, one stop bit, no parity, 5 ms character delay, 20 ms line delay for papertape upload.. Higher baudrates may work.
For CP/M there are many emulators available, choose one that allows file from the PC to be accessed also by the emulator. E.g. the Z80 IDE and CP.M emulator of Hein Pragt.
CC65
I only use the assembler and linker of the CC65 package. Mainly for KIM-1 KB9 Basic development, as the source from Pagetable is in this format.
This is how I do it (Windows, can be done also on Linux)
- Download and unpack the archive of pagetable in a folder on your PC.
- Download and unpack the CC65 package, a C compiler, from which only the assembler and linker is used. I used the Windows binary.
- Copy CA65.EXE, LD65.EXE and longbranch.mac from the CC65 package to the folder where you unpacked the MS Basic source.
- Change whatever you like in the source. It is quite a complicated construction, with macros for every variant, so look carefully at the listing file what really is produced.
Start with no adaptations and then go on studying the listing file and testing. The KIM-1 Simulator is a good tool for testing! Load the symbol table file to see what is where. - Assemble and link with this simple batch file makekb9v2.bat, resulting in an object, a binary, a listing file and a symbol label file.
ca65 -D kb9 msbasic.s -o tmp/kb9v2.o -l tmp/kb9v2.lst ld65 -C kb9.cfg tmp/kb9v2.o -o tmp/kb9v2.bin -Ln tmp/kb9v2.lbl
- Repeat step 4 and 5 until you are satisfied with the adaptations. The article listed above are a good source of inspiration.
Winmerge
A tool to compare files, text and binary. Open the program, drop binary files from the explorer on it and see the differences highlighted. Essential to compare ROM dumps or to check if assembler source assembly leads to identical binary as the original. Detects subtle syntax differences from sources converted or disassembled, leading to different code.
Disassembler
Still searching for a good multiprocessor tool. With some intelligence, like input files not only binary, but also a symbol file and tips of what is data and what is code. Output should be in assembler format ready to assemble. A multipass operation, where you learn from each iteration symbols and data areas.
For 6502 code I use the online tool at Virtual Disassembler. Drop the binary and copy the code. Choose the output format, like “listing” or “assembler”. You can input a symbol file.
See also:
Elektor Junior ASSM/TED
KIM-1 Macro Assembler Editor
MAE ASSM/TED CW Moser
SYM-1 RAE
PRDIS, Printing Disassembler
In 1982 I wrote/composed a program to have disassembled code on paper, with page numbers. Read more about it here.
The core routine of the disassembler is the well-known Steve Wozniak/Allen Baum 1976 article A 6502 Disassembler from Apple
The program is a TTY program. I build it with the then current hardware and software of my KIM-1:
- 32K RAM from $2000
- Video terminal uppercase 24×32 on the KIM TTY serial in/output
- A parallel ASCII keyboard connected to the second 6532 RIOT port
- A serial connected, at 9600 baud, Heathkit H14 matrix printer
- Dual audio cassette records under motor control
- MICRO ADE assembler/Editor, extended and with video TTY as output, parallel keyboard as input and could print at the H14 printer
See also:
Focal-65 V3D for TIM and KIM-1
John Bell Engineering catalogs
New KIM-1 info and more
KIM-1 Simulator simple demo
Printing Disassembler
In 1982 I wrote/composed a program to have disassembled code on paper, with page numbers.
The core routine of the disassembler is the well-known Steve Wozniak/Allen Baum 1976 article A 6502 Disassembler from Apple
The program is a TTY program. I build it with the then current hardware and software of my KIM-1:
- 32K RAM from $2000
- Video terminal uppercase 24×32 on the KIM TTY serial in/output
- A parallel ASCII keyboard connected to the second 6532 RIOT port
- A serial connected, at 9600 baud, Heathkit H14 matrix printer
- Dual audio cassette records under motor control
- MICRO ADE assembler/Editor, extended and with video TTY as output, parallel keyboard as input and could print at the H14 printer
Only the KIM-1 survived today this setup and is now on display above my desk in an acryl case. Most of the software is converted from tape and is on this site in the KIM Software page.
The program was written to have a disassembled printed listing of software like the Microsoft Basic KB9 and other binary only software, so I could analyze, make notes and patch it at will to my hardware and more. It was located at location $B000, out of the way of where most programs were loaded, like $0400 or $2000.
The program prompts for output to video or to video + printer. If printer is selected the output will be paginated with page numbers and it asks for a header text.
I still have the printed output of Microsoft Basic with my hand written notes on it.
The original source and binary (restored from cassette, the previous version on the website was incomplete):
Printing disassembler, load and start address is $B000
Source of disassembler
Requires a parallel keyboard for character input at the free 6530 PIA port. H14 printer output if print is requested.
As is not fit for a standard KIM-1!
PRDIS Version 2
In January 2023 Glen Deas, K5GED, approached me about this program. He found out the binary was missing the last bytes (now corrected). He also showed me how he converted the MICRO ADE source to AS65 format and made it use the KIM-1 standard TTY I/O again.
Printing disassembler, load and start address is $B000 for KIM-1, Glen Deas version
; VERSION 1.1 JANUARY 2023 SYNTAX MODIFIED FOR THE ; A65 CROSS ASSEMBLER GLEN DEAS, K5GED USA INVOKE A65: A65 -L -M -H D6502TTYV2.S ; Version 2.0 MODIFIED TO USE THE KIM-1 SERIAL I/O INSTEAD OF PARALLEL KEYBOARD ; USING KIM'S TTY ROUTINES - BY DEFAULT IT OUTPUTS TO THE VIDEO ; MONITOR/TTY VIA THE OUTCHK CALL TO THE KIM-1 MONITOR ; Set up Procomm up for 7 data, Mark parity, and 2 stop bits, no echo
PRDIS Version 3
I could not resist to spent an afternoon on the source Glen Deas has given me. So much fun to work on code 40 years later. Grateful to Glen for his work on his vesion.
Here is my latest version, running fine in the KIM-1 Simulator.
Source and binary in papertape format V3 of PRDIS
Improvements in V3:
- No problems with echo or 7 bit anymore, all standard KIM-1 monitor
- Lowercase messages
- Code for H14 printer or parallel keyboard commented out, reducing size
- Rommable, variables moved to RAM $0200, program at $B000
- Stops output after every 16 lines, any key but Enter stops program
- Source formatted and syntax for TASM32, license added
Example session, PRDIS disassembling itself without and with Pagination:
KIM B000 D8 G Printing Disassembler V3.0 for 6502 Printer or video format (p/V)? Address range (XXXX-YYYY)? B000-B100 Disassembly: B000 D8 CLD B001 A2 FF LDX #$FF B003 9A TXS B004 A9 01 LDA #$01 B006 8D 00 02 STA $0200 B009 A9 00 LDA #$00 B00B 85 EE STA $EE . . . B0F6 C9 22 CMP #$22 B0F8 F0 13 BEQ $B10D B0FA 29 07 AND #$07 B0FC 09 80 ORA #$80 B0FE 4A LSR B0FF AA TAX KIM B000 D8 G Printing Disassembler V3.0 for 6502 Printer or video format (p/V)? P Address range (XXXX-YYYY)? B000-B200 Header text? PRINTING DISASSEMBLER PRINTING DISASSEMBLER Page 01 B000 D8 CLD B001 A2 FF LDX #$FF B003 9A TXS B004 A9 01 LDA #$01 B006 8D 00 02 STA $0200 B009 A9 00 LDA #$00 B00B 85 EE STA $EE B00D 8D 01 02 STA $0201 B010 20 2A B3 JSR $B32A B013 A2 B4 LDX #$B4 B015 A0 AC LDY #$AC . . . B1C6 60 RTS B1C7 A5 F0 LDA $F0 B1C9 38 SEC PRINTING DISASMBLER Page 05 B1CA A4 FB LDY $FB B1CC AA TAX B1CD 10 01 BPL $B1D0 B1CF 88 DEY . . . B1F9 33 ??? B1FA D0 8C BNE $B188 B1FC 44 ??? B1FD 00 BRK B1FE 11 22 ORA ($22),Y KIM B000 D8
See also:
Elektor Junior ASSM/TED
KIM-1 Macro Assembler Editor
MAE ASSM/TED CW Moser
SYM-1 RAE
Corsham Bus Extender
Corsham Technologies produces a Bus Extender fot the KIM-1. SImple but so handy.
It is placed beween the external device on Application or Extension Connector and has 44 pin header to attach wires to a breadboard for example.
Only negative I can say about it, tinned edge connectors and not gold plated.
Nice addition to my Reproduction KIM-1s!
See also:
Focal-65 V3D for TIM and KIM-1
John Bell Engineering catalogs
New KIM-1 info and more
KIM-1 Simulator simple demo
MOS KIM-1 Reproduction, white version
Dave Wiliams made a revison of the MOS KIM-1 Reproduction, a white version.
The original green and the new white are for sale at ebay as of January 2023.
See also:
Focal-65 V3D for TIM and KIM-1
John Bell Engineering catalogs
New KIM-1 info and more
KIM-1 Simulator simple demo
AIM 65 clone
Mr. Nagano, from Tokyo, Japan send me photos and circuit diagram of an AIM 65 clone he built. It is a beautiful and functionally and esthetic faithful clone. In fact, he built two, one with a CPLD 3V3 version and a 5 V version with a 6532 RIOT.