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Comment by TacticalCoder

12 hours ago

TFA lacks a picture of the TI-99/4a. I've got one and it's such a beautiful machine:

https://commons.wikimedia.org/wiki/Category:Texas_Instrument...

There was also a beige version released later (http://www.mainbyte.com/ti99/computers/ti99beige.html). I have both variants in my collection and they're both attractive machines, especially by the standards of the early 80s. The best part of the design was that it had a decent keyboard (unlike its predecessor the TI-99/4, which is much more rare - and for good reason). It also was the first home computer to have hardware graphics support in the form of TI's home-grown TMS9918 VDP chip which outlived the computer it was made for by many years. It was used in dozens of different 8-bit computer models from manufacturers around the world and spawned several improved variants, including the graphics chip in the Sega Master System console!

Unfortunately, the 99/4a was brutally hobbled by some bizarre design choices that nerfed its performance including forcing the 16-bit CPU onto an 8-bit system bus which halted the CPU to spread each 16-bit read/write into two sequential operations. This was made worse by the fact the CPU used a memory-to-memory architecture (even for most of its own registers) and all the memory was behind that '8-bit wall' - except for 256 bytes of 'fast scratchpad' (aka just 'normal memory' on other 8-bits). Plus the GROM was on PROM chips that were even slower than RAM, introducing more latency.

The whole GROM thing could have been a nice idea if it weren't for the 8-bit bus and slow PROM chip speed. Unfortunately, TI execs were more interested in finding a home for excess PROM chip inventory than making their home computer the best it could be. So, it was hard to extract high-performance game graphics from the system, requiring significant ingenuity from developers.

I convinced my grandfather to give me $30 to buy one at a garage sale while i was house sitting with him (he had emphysema and was 82 at the time) back in the early 90s. he lived as an adult through the depression, so it was a point of contention between him, me, and my mom. It only came with 1 cartridge iirc, and a brochure showing all the accoutrements you could add to it, speech module, joystick, and i forget what else.

turning it on and getting a BASIC prompt was real cool. never could save anything, though. I traded it in 1999 or so for an Apple IIc with monitor, with which i could save data.

coincidentally, i just mentioned owning a ti-99/4a to a friend yesterday, we were comparing notes about the first computers we actually owned, and that was it, for me. We had an atari (the wood paneled console one, carts, with keyboard built in, BASIC interpreter on ROM) in '87ish i guess, but i only had it for a couple of weeks before i accidentally blew it up with a cable trying to save something to a tape recorder. the tape recorder had a cable in the back that had a 1/8" TS plug, which apparently was a radio shack "universal power supply" and i guess i put 9VDC into the speaker port.

  • To save you either needed a cassette recorder, plugged into the machine with a special cable, then "SAVE CS1" and follow the instructions. (Start recording, the TI plays sound to the output port, which gets stored on tape. Use "LOAD CS1" to load from cassette, after rewinding to the start of the program.)

    Or you needed an expansion box, with a floppy drive, in which case you could do "SAVE DSK1,PROGNAME" to save to "PROGNAME" on the first disk. I didn't have an expansion box.

    Neither would have come with the base computer.