Geneve 9640 - the "other" TMS9900 based micro

As noted in a thread elsewhere, when TI failed to capitalise on their 9900 CPU in their TI-99/4(a) computers, a company called Myarc which had made addons for those designed and eventually sold their own bigger, better, compatible machine, the Geneve:

Image from Fabrice Montupet’s site here, with even more content in the francophone section of the site.

See also old-computers on this machine, and the extended story of the Geneve here.

Over on the mastodon thread, Paradroyd notes the popularity of the Heatwave BBS which actually runs on a vintage Myarc Geneve 9640 built in 1987.

For additional background on the very interesting history within TI, see the article
The Inside Story of Texas Instruments’ Biggest Blunder: The TMS9900 Microprocessor


There was also the Tomy Tutor which used the same chips as the TI99/4A. More links at Wikipedia.

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Oh, good find! Sounds like quite a well-rounded offering. Using a different incarnation of GPL, the mid-level interpreted language, a kind of bytecode perhaps.
Some technical info on the Basic and the so-called Monitor:

There was also an S-100 CPU board with the 9900:
I believe there was an earlier eval board, too, but can’t find a reference now.

Wow, another very rare find! I suspect there weren’t many 16-bit CPUs found on S-100 systems. But I’m ready to be wrong about that!

The goal of the Graphics Programming Language was to isolate the programmers from the complexity of using the various memories in the machine. The 128 words of RAM and built-in system and GPL ROMs were simple enough, but the 16KB of video memory required writing the address to a 9918 register in two halves and the reading or writing the actual byte from another register. Accessing the Basic and cartridge ROMs was just as complicated.

Tiny Basic was implemented as an interpreter written in an imaginary language (IL) which in turn was implemented as an interpreter in machine language. So TI did the same for its Basic and used the opportunity to make all those odd memories look normal not only for Basic itself but for any cartridges.

Besides the 9900 S100 board mentioned, the same site shows the 8086 machine for which QDOS (which later became MS-DOS) was developed, a more integrated 8086/8087 board, a 286 board, another 8086 board, a 68008 board, a 8088 board, a hybrid Z80/286 board, a 186 board, a 68000 board, a hybrid Z80/68000 board and another 186 board.

But the most options were offered by Compupro, with S100 boards including the hybrid 8085/8088, the 8086/8087, the 286, the 186, the 68000 and the 32016.

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GPL strikes me almost like a wonderland version of Sweet16: it provides access to byte-oriented memory and runs on a word-oriented 16 bit MPU. (And yes, I see there are three memory spaces as seen by GPL: CPU memory, Video memory, and G memory.) Here’s some documentation:

(Of course, the above is about TI’s GPL, not Tomy’s.)

For those who like that kind of thing, there’s a go-faster FPGA implementation of the 9900 here:

Going through some old magazines I ran across this ad in the Oct 79 issue of Kilobaud.