Model: CompuChess
Manufacturer: DataCash / Staid, Inc.
Year: 1977 (December)
Est. ELO rating: 1000?
Levels of play: 6
Type: Calculator

(click on pictures to enlarge them)

CompuChess by DataCash / Staid, Inc.
This is one of the very first chess computers (or electronic chess) to be sold. It's from 1977, the same year the very first commercial chess computer was introduced: the Fidelity Chess Challenger 1.  The manual says the company is Staid Inc. I have seen references to DataCash as being another company producing this chess computer. From the information I was able to gather, both companies were part of the same business.

The manual calls the levels of play "levels of intelligence". I does handle castling, en passant. In level 6, it can take up to two days for the computer to respond!

Here is a list of the chips inside this unit:

1) NS/642 LM 390 9N
2) NS 541 DS75492N
3) NEC JAPAN E78036-733 D2101AL-4
4) NEC JAPAN E78036-733 D2101AL-4
5) 32014-4950 CMCSI/STAID 7741 TAIWAN
6) 3853PC F 7734 SINGAPORE
7) SPRAGE 7529 ULN2033A
8) 3850PK F 7739 SINGAPORE

Researching the components I got this information (thanks Doug!):

3850PK (Fairchild F8 CPU; apparently commonly used in those days for small specialized computers like this)

3853PK (Fairchild Static Memory Interface)

(2) NEC D2101AL-4 (256x4 Static RAM; 2 chips made a whopping 256 bytes of RAM!)

CMCSI/STAID 32014-4950 (Being the only chip imprinted with the name of the CompuChess manufacturer, it must be the ROM that contains the code for the chess program, custom produced for them by a chip company. I could not find any specs on what the memory capacity of the chip might be. If it's any more than 4K I would be amazed.)

75492 (standard TTL chip - 6 Digit MOS to LED Cathode Driver, of which only 4 are used of course)

ULN2033A (7-Darlington transistor array, probably to drive the seven LED anodes that make up each digit)

LM3909N - (LED Flasher oscillator, most likely used to flash the decimal points of the display when an entry error is detected)

One thing about this model is that it has a very interesting "feature": it accepts and occasionally makes illegal moves!

A legal battle was fought because of copyright issues here. DATA CASH Systems, Inc. v. JS&A Group, Inc., et al. ( http://newpaltz.edu/~zuckerpr/cases/data-chs.htm )

Final pagragraph from that rulling:

Since the parties have assumed that the ROM is a "copy" of plaintiff's computer program, they have perceived the issue here to be whether the sale of the CompuChess, which contains the ROM, was a publication of the computer program. Since the court concludes that the ROM is not a "copy" of the computer program, it need not reach this issue.

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