KIM-1 related updates

KIM-1s, not made by Commodore but nearly identical.

More photos at the KIM-1 related page

KIM-1 keyboard repair

The KIM-1 keyboard is a special one. Made especiallyfor the KIM-1, as you can see in the SST switch. It shows its age in the design, and looks quite familiar to the keyboards hand-held calculators of the 70ties.

In those days replacement keyboards could be bought. I have repaired several KIM-1s with it. The older revisions were worse than what appeared on later revisions.

See also this page about KIM-1 keyboard repair, local copy here.

Original KIM-1 version, SST switch on the right.

KIM-1 Rev D, SST switch on the left.

The keyboard is connected to the mainboard with two screws, as you can see on the next image, and the solder connections on the front of the motherboard to the top of the keyboard.
You also see seven holes with access to screws on the bottom of the keyboard. Those keys hold the top of the keyboard connected to the bottom part. Unscrew those seven to get inside the keyboard. Leave the two screws not in a hole alone!

Over time the keyboard may develop problems like stick keys and non-responsive keys. Due to wear or dirty contacts.

A post in the vcfed.org forum may be helpful to fix some of these problems.

User Mindwalker posted this:

I (mindwalker) remember cleaning the keyboard at one point and I found this picture from my archives.
It seems the key membrane connects to the PCB over four contacts right on the bottom row, you probably have a bad contact there. Cleaning and (carefully) tightening the screws may cure it! Just be careful with the membrane.

Or you could replace the keyboard with other keypads:

An article in KIM User Notes 10/11 has this advice for the first Revisions key (No Revision, Rev A, Rev B):

Construction of a nearly exact KIM-1 replica keyboard.

Original version: Design, images and original text in German by Ralf (ralf02, forum64.de), from the KIM-1 Aufbau anleitung, and KIM-1 Keypad by user hackup, October 30, 2022 on thingiverse

Circuit diagram of the Keyboard PCB

For the keyboard construction you need the following parts:

  • 1 3D printed keyboard frame, STL from thingiverse
  • 2 keypads with 16 keys each as shown (actually, you just need 1 1/2)
  • 1 keypad PCB, see the gerber file
  • 1 SPDT slide switch, 2.54mm pitch
  • 1 female pinheader connector, 15 pins, preferably low profile
  • 1 male pinheader, 15 pins to match the female one
  • 6 self tapping screws, 2x6mm
  • labels printed white on black for the keys E, F, AD, DA, PC, +, GO, ST, RS
  • double sided adhesive tape to glue the clips to the motherboard

The keyboard PCB has to be gold plated (ENIG). With tin-plated PCBs the contact from the keys is not reliable.

Downloads made available by Ralf:

First dismantle the two keyboards and cut the two rubber contact mats as seen in the next picture. Keys 0-0 and A-D have the right lettering, make the other with a letter printer white on black.

Place the keycaps in the 3D printed case:

Now solder the slide switch and the pinheader on the PCB. Cut the rubber mat on the location of the slide swithc. Put the mat in the 3d printed case and fix with 6 screws:

Next place the four M3 screws in the holes in the PCB and the parts in the case. Now place the PCB on the 1 pin pinheader and fix the four screws with washers from the bottom.



The two red wires are only for decoration, to make it look like as on the KIM-1.

KIM-1 keyboard repair

The KIM-1 keyboard is a special one. Made especially for the KIM-1, as you can see in the SST switch. It shows its age in the design, and looks quite familiar to the keyboards hand-held calculators of the 70ties.

In those days replacement keyboards could be bought. I have repaired several KIM-1s with it. The older revisions were worse than what appeared on later revisions.\
Read this page how to repair some common problems.

Scanned book: Anwendungsbeispiele für den Mikroprozessor 6502

Anwendungsbeispiele für den Mikroprozessor 6502
Herwig Feichtinger

Hardware-Tips und nützliche Programmierbeispeile in Maschinensprache


KIM-1 Simulator V1.1.2

Updates for the KIM-1 Simulator, now V1.1.2
– KIMDLe runs, with free running timer for randomizer (first step towards working timer emulation) and fix of KIM Keyboard return value of No key $15
– Fixes for console keyboard handling, German and International settings and uppercase/lowercase handling, width character font now 1 pixel different for Linux and Windows
– Testkeydown first line bug

Executables for Windows, Ubuntu and Raspberry PI OS, sources for Lazarus

MCS6500 Microcomputer Family Programming Manual


High-res quality typeset manual by Pickledlight. Local copy. Check to original for updates!
MCS6500 Microcomputer Family Programming Manual
MCS6500 Microcomputer Family Programming Manual Hardcover

Pocket calculator for the KIM-1


Siep de Vries Westvries Computing The Netherlands 1977

Simple calculator (integer 6 digits positive) + – / *

I/O via TTY or keypad/LED display, the same method as used by the KIM-1 monitor.

Two versions (scans included): a special publication from the first days of the KIM Club in a traditional 6502 assembler and a later version for the Micro ADE assembler editor.

The versions are functionally identical, the memory layout of zeropage is different.

Sources included of both versions (TASM 32), with resulting listing and papertape and Intel hex files.
As close to paper original, changes due to assembler quirks.

Usage:
– Load papertape
– choose TTY or keypad/LED via switch

– Input is given by entering a decimal number followed by a function key
(only + – / * seems to work)

Functions (first KIM-1 keypad, second TTY keyboard)
A = + = add number to result
B = – = subtract number from result
C = * = multiply result by number
D = / = divide result by number
E = c = clear input number
F = A = clear result
AD = r = remainder of last division
DA = i = number stored in memory
+ = c = number from memory
PC = % = calculate percentage
GO = C = clear result

? displayed means integer arithmetic error (overflow or negative)

Hans Otten, 2021 – 2022
Tested and Screenshots made with theKIM-1 Simulator

KIM-1 Simulator Version 1.0

KIM-1 Simulator Version 1.0, out of beta, all planned functionality implemented. Console has now ANSI color mode subset implemented.

Convert hex formats and KIM-1 Simulator KIM-1 audio tape support

Both Convert 8 bit hex formats and the KIM-1 Simulator now support the emulation of KIM-1 audio tapes. All available and tested on Windows, Ubuntu and Raspberry PI OS.

 

 

KIM-1 Simulator, another update

I keep on working on this program, so much fun letting the old KIM-1 experience come alive again.

0.13.1 brings tape support in the KIM-1 way: you enter the start address, end addres and tape ID and strat the tape save at location 1800, load from 1873.

A popup appears to choose file to laod/save form, while the KIM-1 waits for the laod and save to finish. Success or failure is reported as the KIM-1 monitor does: 0000 (OK) or FFFF (not OK) as address.

Also the main screen has seen some updates, the console is bigger and one can choose fore and background colior.Many VT100 cursor control works now, more to come.
Tasting and building now on Windows, Raspberry PI OS and Ubuntu.

Work planned:
– color managing in Console to allow reverse video, coloured characters, more VT100/ANSI ESCape support.
– add tape file support to the general memory laod and save routines, also in the Convert 8 bit hex formats program.
– thinking how to add 6532 timer support

Enjoy and tell me what you think!