John Graham-Cumming’s weblog: My 1976 KIM-1

2023-11-06 06:24:43

Some years in the past I wrote about programming a KIM-1 in 1985. By that point the KIM-1 was outdated, and positively not state-of-the-art. In spite of everything, it was launched in 1976.

Nevertheless it’s a machine I loved programming (which required punching in code by way of the hex keypad, or, when you had been fortunate, connecting a terminal (by way of a 20mA present loop designed to speak to an precise Teletype) to it and utilizing the very fundamental monitor program). The KIM-1 may additionally interface to a paper-tape reader/punch and a cassette for storing and loading applications.

I’ve a tiny assortment of machines that matter in my private computing historical past: a Sharp MZ-80K, a Analysis Machines 380Z, a Analysis Machines 480Z, my original BBC Micro and a KIM-1 (that is an image of my machine above). The (totally working) KIM-1 was made in 1976 and is serial quantity 2,793. It is nonetheless sitting in its unique packaging:

(I added the protecting perspex case)

You’ll be able to simply make out that it is described for customs’ functions as a “KIM-1 System” with a price of $245 (about $1,315 as we speak; roughly the price of a present MacBook Air 15″ laptop computer). Postage was $4.75 from the US to Europe.

The serial quantity is on each the PCB and the field. The field notes that it was checked on July 27, 1976 and the just about illegible submit code appears to point it was posted two days later.

The date codes on the MOS chips are as follows: 2776 (week 27 of 1976) on the 6502 processor, 1776 (week 17) on one of many 6530s and 1876 (week 18) on the opposite. The week quantity for the 6502 is necessary as a result of apparently 6502s made as much as week 26 had faults! (It is also the case that week 27 of 1976 ended July 4, 1976… the 200 yr anniversary of the US Declaration of Independence).

The machine got here with a set of manuals and a helpful circuit diagram. The circuit diagram is poster dimension.

The three manuals cowl the {hardware} (together with the entire MCS650X household of chips and specifics of interfacing to the KIM-1 from gadgets like a Teletype), utilizing the KIM-1 (together with debugging {hardware} faults, interfacing a paper-tape reader and cassette and use of the in-built monitor program) and programming the KIM-1 (this handbook is an entire reference to 6502 programming). One aim of the KIM-1 was to introduce the 6502 and associated chips and to make it possible for everybody may perceive and use them (and design them into their very own merchandise).