In
a previous article I discussed the MOS 7600 and 7601 "Pong in a chip" ICs, manufactured by MOS Technology (of the famous 6502) and actually used in a number of late 1970s Pong clones, including two that eventual parent company Commodore Business Machines
sold under their own name. Most notably they appeared in the Coleco Telstar Arcade console, an unusual "triangular" machine in which specific variants of the 7600 were used as its cartridges, but were also used in a number of other Pong clones through around 1978.
The question at the time was whether the 7600 actually had ROM in it (i.e., was a true microcontroller running a stored program), or whether it was simply playing games using discrete circuitry. The Telstar Arcade — and its relative, the confusingly named Telstar Gemini, not to be confused with the separate Coleco Gemini — demonstrated that other variants of the 7600 were capable of more sophisticated games than just ball-and-bat Pong variations, including primitive versions of pinball and road racing, even though most systems using the 7600 used it purely for Pong. On the other hand, no data sheets have survived to the present day and at the time my Google-fu uncovered no die photos to review, so I could find no substantiation for the occasional claims that it did.
Well, we now definitively know the answer and a bit more thanks to Sean Riddle, who actually did decap and photograph a 7600-002 die (the variant in Telstar cartridge #1, with racing, Pong and skeet shooting) and a 7600-001 (the most common three-Pong-and-skeet variant used in many machines, as well as in Telstar cartridge #2), and to Ken Shirriff, who made an extensive survey of the die, discussed with Sean and I attributes he noted, and posted a thread about it. Here's my own summary of the discussion plus a few other details I've run across since writing the original post.