KIM-1 case

The KIM-1 came from MOS Technology and Commodore without a case or power supply. So you either build your own housing or looked at what other firms sold for the KIM-1.
There was a lot on offer, mostly targeted at system expansion with large cases.

One of the cases you saw quite often was this case. It came with one of my KIM-1’s. Small, simple and effective

A perfect solution for an unexpanded KIM-1. Quite popular in education. Add a power supply and you can start using it without exposing the electronics. The LED display was behind a red plexiglas cover, so that improves readability.

B.E.M. photos made by Gerben Voort

Brutech, a small Dutch company, made industrial quality microprocessor systems. 6502, 6809, process control.

Gerben Voort acquired a 6502 system and made photos of the system. A backplane, the BEM bus, a 6502 based CPU card, a double VIA card, a battery backed up memory card.
Read more about Brutech here.

KIM-1, what changed in the Revisions?

I know of seven KIM-1 revisions, labeled Rev A-G and the first one unlabeled. Rev C is unknown!

What changed between these revisions?

Not much. The PCB underwent several changes around the logo area, from KIM-1 MOS to Commodore C-MOS. That happened from Rev A to Rev D, indicating the takeover by Commodore of MOS Technology. And some small numbers/artefacts etched in various Revs. The big change was in the clock circuit between the first edition and Rev A.

Some have serial numbers, the first ones on the back on the right, later had stamped/written numbers like PAxxx (Palo Alto) and SCxxx (Santa Clara) of Commodore production facilities

Clock circuit change
The first batch of KIM-1 suffered from the issue that the clock would not start. It was fixed in Rev A, with more components and a change in PCB layout.

Read more

Jolt replica by Eduardo Casino

Eduardo Casino has created a faithful replica of the Jolt single board computer. Tested! Working!
The replica design is available on GitHub, A faithful reproduction of the JOLT

More on the Jolt here.

A faithful replica of the Microcomputer Associates Inc. JOLT computer, based on photos and information gathered from various sources on the internet.

The JOLT was the first 6502‑based computer kit to be commercially released, beating the KIM‑1 to market by several weeks; the latter would launch in January of the following year. It is a small SBC featuring a 6820 PIA and the 6530‑004 RIOT, also known as TIM‑1. It includes 512 bytes of RAM, a teletype interface, and an RS‑232 interface. The 6530‑004 contains, in its 1K ROM, the monitor software DEMON, also simply referred to as TIM.

New versions of KIM-1 Simulator V2.0.0 and TIM Simulator V0.9

The KIM-1 Simulator has seen a large update.
A new piece of hardware is added, the SD Card/RTC Shield by Corsham Technology.
This addition has been written by Eduardo Casino. Lots of code contributed, thanks Eduardo!
He also added support for two operating systems using the SD Shield, xKIM by Bob Applegate and CP/M-65 by David Given.

The problem with local language keyboard layouts is solved by Eduardo. Now the host operating system takes care of the different layout.

The documentation has been enhanced and moved from a local limited html file to an online version.

Enjoy! See it here.

The keyboard and online improvements have been ported by me to the TIM/Jolt Simulator.

Download it here.

XKIM on the KIM-1 Simulator

xKIM is developed by Bob Applegate to support his SD-Shield.
By adding SD Card/RTC Shield support to the KIM-1 Simulator by Eduardo Casino we can run xKIM there now!

KIM                                                                                              
0200 00                                                                                          
0201 48                                                                                          
E000 
E000 4C G

Extended KIM Monitor v1.8 by Corsham Technologies, LLC
www.corshamtech.com

>?
Available commands:

  ? ........... Show this help
  C ........... Show clock
  D ........... Disk directory
  E xxxx ...... Edit memory
  H xxxx xxxx . Hex dump memory
  J xxxx ...... Jump to address
  K ........... Go to KIM monitor
  L ........... Load HEX file
  M xxxx xxxx . Memory test
  O xxxx xxxx . Calculate branch offset
  P ........... Ping disk controller
  S xxxx xxxx . Save memory to file
  T ........... Type disk file
  K ........... Go to KIM monitor
  ! ........... Do a cold start


>C
Date: 03/25/2026, 15:16:47

>Disk Directory...
   bootsdshield-kimrom.bin
   bootsdshield.bin
   bootsdshield.pap
   CPM-BOOT.DSK
   kb9.ihex
   KIM-1 simulator start.jpg
   kim-1-sdshield.zip
   kimsimSETTINGS.jpg
   M2000.BIN
   newimage.dsk
   SD.cfg
   SDMP1.jpg
   SDMP2.jpg
   SDMP3.jpg
   SDMP4.jpg
   SDMP5.jpg

>T - Enter filename: SD.CFG
# SD Card Disk Configuration
# Format: drive:filename or driveR:filename (for read-only)
0:CPM-BOOT.DSK
1:newimage.dsk

>S 2000-2199
Enter filename, or Enter to display to console: K2000.BIN
..........................
>Disk Directory...
   bootsdshield-kimrom.bin
   bootsdshield.bin
   bootsdshield.pap
   CPM-BOOT.DSK
   K2000.BIN
   kb9.ihex
   KIM-1 simulator start.jpg
   kim-1-sdshield.zip
   kimsimSETTINGS.jpg
   M2000.BIN
   newimage.dsk
   SD.cfg
   SDMP1.jpg
   SDMP2.jpg
   SDMP3.jpg
   SDMP4.jpg
   SDMP5.jpg

>T - Enter filename: M2000.BIN
:102000001510922D4C000020902860A00CA900997A
:10201000922D8810FA4CD425A9FF8D942DA9008DFE
:102020009E2D60084898488A48AD942D3004A00041
:10203000911A68AA68A8682860A51A49FF2D952DED
:102040008D952DA51B49FF2D962D8D962D18602061
:10205000CD20A90F204325B02BA00CB11A8522A0BA
:102060001FB10E911A8810F920A923A00CB11AC52E
:1020700022F00AA9009002A980A00F911AA522A01F
:102080000C911A186020CD20206428A90F20432528
:102090009037A900A010911AC8C020D0F9A9E5A0D6
:1020A00000911AA901204325B01FA001B11A910E79
:1020B000C8C020D0F7ADB12DA000910E20AF26A949
:1020C0000120D22720A9231860A9FF3860A00EA9FB
:1020D00000911AA000B11A8D942D290FAACA1003DD
:1020E000AEB02DADB12D911A8A4CD42520D320202D
:1020F000A625206428A00EB11A10021860A90F208E
:01210000439B
:00000001FF
>
>L
Enter filename, or Enter to load from console: m2000.bin
.................
Success!

CP/M-65 on the KIM-1 and KIM-1 Simulator


Thanks to the work of David Given (who developed CP/M-65) and Eduardo Casino (who ported CP/M-65 to the KIM-1 with the SD-Shield (developed by Bob Applegate of Corsham Technology) and the addition of the SD-Shield simulation to the KIM-1 Simulator by Eduardo Casino I can run my Pascal-M compiler (written by Mark Rustad in 1977 and ported my Hans Otten to Lazarus and ported by david Given to CP/M-65)) on my PC in the KIM-1 Simulator (developed by me Hans Otten since 2019) compiling itself and showing it can compile ‘hello world’ program.

Pfff, long sentence showing that all this is made possible by many clever people!

Here a log of a session (captured by Teraterm connected to the KIM-1 Simulator).

KIM                                                   
0200 D8                                               
KIM                                                   
0200 D8 G                                             
                                                      
CP/M-65 for the KIM-1                                 
                                                      
A>dir                                                 
A: SCRVT100 COM : IMU      COM                        
A: IMU      TXT : SYS      COM                        
A: PASC     PAS : ASM      TXT                        
A: HELLO    ASM : DEMO     SUB                        
A: ASM      COM : ATTR     COM                        
A: BEDIT    COM : CAPSDRV  COM                        
A: COPY     COM : CPUINFO  COM                        
A: DEVICES  COM : DINFO    COM                        
A: DUMP     COM : LS       COM                        
A: STAT     COM : SUBMIT   COM                        
A: MORE     COM : BEDIT    ASM                        
A: BEDIT    TXT : DUMP     ASM                        
A: LS       ASM : CPM65    INC                        
A: DRIVERS  INC : ATBASIC  COM                        
A: ATBASIC  TXT : OBJDUMP  COM                        
A: MKFS     COM : ADM3ADRV COM                        
A: ADM3ATST COM : CLS      COM                        
A: LIFE     COM : QE       COM                        
A: SCRNTEST COM : VT52DRV  COM                        
A: VT52TEST COM : KBDTEST  COM                        
A: MBROT    COM : DS       COM                        
A: DS       TXT : PINT     COM                        
A: PASC     OBB : PLOAD    COM                        
A: HELLO    PAS : IMU3     TXT                        
A: HELLO    SYM                                       
                                                      
A>pint PASC.OBB PASC.PAS PASC.OBS                     
Pascal-M interpreter for CP/M-65: B66F bytes free     
Pascal-M compiler V2k1 for CP/M-65                    
Processing: writeerr                                  
Processing: beginlin                                  
Processing: endline                                   
Processing: error                                     
Processing: stringsi                                  
Processing: nextchar                                  
Processing: insymbol                                  
Processing: enterid                                   
Processing: searchse                                  
Processing: searchid                                  
Processing: getbound                                  
Processing: hexout                                    
Processing: writeout                                  
Processing: bytegen                                   
Processing: wordgen                                   
Processing: genujpen                                  
Processing: plantwor                                  
Processing: skip                                      
Processing: test1                                     
Processing: test2                                     
Processing: intest                                    
Processing: constant                                  
Processing: comptype                                  
Processing: isstring                                  
Processing: simplety                                  
Processing: fieldlis                                  
Processing: typ                                       
Processing: constdec                                  
Processing: typedecl                                  
Processing: vardecla                                  
Processing: paramete                                  
Processing: procdecl                                  
Processing: ldcigen                                   
Processing: ldagen                                    
Processing: lodgen                                    
Processing: condgen                                   
Processing: loadsetc                                  
Processing: cspgen                                    
Processing: incgen                                    
Processing: load                                      
Processing: store                                     
Processing: loadaddr                                  
Processing: falsejum                                  
Processing: calluser                                  
Processing: selector                                  
Processing: variable                                  
Processing: processt                                  
Processing: readproc                                  
Processing: processt                                  
Processing: writepro                                  
Processing: newstate                                  
Processing: releases                                  
Processing: resetrew                                  
Processing: closepro                                  
Processing: assignpr                                  
Processing: getcomma                                  
Processing: ordfunc                                   
Processing: succfunc                                  
Processing: predfunc                                  
Processing: chrfunc                                   
Processing: oddfunc                                   
Processing: eofeolns                                  
Processing: callnons                                  
Processing: call                                      
Processing: opgen                                     
Processing: setexpre                                  
Processing: factor                                    
Processing: term                                      
Processing: simpleex                                  
Processing: expressi                                  
Processing: assignme                                  
Processing: compound                                  
Processing: ifstatem                                  
Processing: casestat                                  
Processing: repeatst                                  
Processing: whilesta                                  
Processing: forstate                                  
Processing: statemen                                  
Processing: body                                      
Processing: block                                     
Processing: stdnames                                  
Processing: enterstd                                  
Processing: enterstn                                  
Processing: enterund                                  
Processing: initiali                                  
Processing: compileh                                  
Processing: compilep                                  
Processing: skipspac                                  
Processing: getword                                   
Processing: findend                                   
Processing: openfile                                  
Processing: closefil                                  
Processing: dumperro                                  
Processing: cpascalm                                  
Compilation successful.                               
No compilation errors PASC.PAS                        
                                                      
A>pload PASC.OBS PASC.OBB                             
Opening input file...                                 
Opening output file...                                
Reading OBP...                                        
Seen 94 procedures                                    
Writing output file...                                
Closing output file...                                
Success.                                              
A>type HELLO.PAS                                      
program HelloWorld;                                   
                                                      
begin                                                 
    writeln('Hello from Pascal!')                     
end.                                                  
                                                      
A>                                                    
A>pint PASC.OBB HELLO.PAS HELLO.OBS                   
Pascal-M interpreter for CP/M-65: B66F bytes free     
Pascal-M compiler V2k1 for CP/M-65                    
Processing: hellowor                                  
Compilation successful.                               
No compilation errors HELLO.PAS                       
                                                      
B>A:pload A:HELLO.OBS HELLO.OBB                       
Opening input file...                                 
Opening output file...                                
Reading OBP...                                        
Seen 1 procedures                                     
Writing output file...                                
Closing output file...                                
Success.                                              
B>A:pint HELLO.OBB                                    
Pascal-M interpreter for CP/M-65: B66F bytes free     
Hello from Pascal!                                    
                                                      
B>                                                    

The White KIM-1

Recently I acquired a ‘white’ KIM-1. Most revisions were made of green PCB material.
Rev D and Rev E were also made in blue.

This one is a Rev D with a ‘white’ PCB. The KIM-1 is working as you can see.

The ‘white’ KIM-1 as received, working but awful to look at

But the previous owner did some horrible work on it. Most IC’s were unsoldered and placed in some kind of IC sockets. The desoldering did quite some damage to print traces.
Many traces were covered with solder. Solder remains everywhere, very dirty brown spots of solder resin. Wires soldered on the connector, and the A-K wire on the board itself.

The biggest crime is the keyboard that was handmade on experimenters board. With quality switches, but with an awful appearance. It works, but it had to go.

With the DIY keypad method, based upon the work of Eduardo Casino and Pete (peo2000) I replaced the keyboard with an acceptable replica. Not too easy and tidy since the print traces were damaged

With a replica keyboard, wires and excessive solder removed and a good clean with alcohol and a brush the white KIM-1 may join my collection.

KIM-1 replica keypad

A spare KIM-1 keypad is even rarer than a KIM-1 itself. With this guide you can build a reasonable replica of the keypad.

Thanks to the work of Eduardo Casino (the PCB) and Pete (peo2000 on forum64.org) I have published a DIY guide for a good looking KIM-1 keypad replica.

A-ONE Apple 1 replica family 2025

In 2025 Franz Achatz revived the A-ONE Apple 1 replica. The excellent design is refreshed, a new family member added: the A-ONE PLUS.

I now have the 2025 standard board, the 2025 PLUS and the 2006 EXTENDED. With the prototype boards with and without breadboard and the 2025 cassette interface.

Read all about the A-ONE here.

My Apple 1 Replica and the A-ONE PLUS