UNIX99, a UNIX-like OS for the TI-99/4A (forums.atariage.com)

95 points by marcodiego 2 hours ago

SoftTalker an hour ago

@UsagiElectric on YouTube has a series of videos on building a homebrew around the TMS9900 processor. Would be cool if a unix-like OS could be used on something like that, though sounds like this project is specifically targeting the TI-99/4A system.

The TI-99/4A was the first computer I owned as a teenager. I had used TRS-80s and Apple ][ at school. I eventually bought the expansion box and a couple of accessory cards (floppy disk drive, memory and RS232). It all went in the e-waste dumpster about 20 years ago during a move.

sunanda35 8 minutes ago

Can you drop this yt channel name?

Brian_K_White 5 minutes ago

you only get 3 guesses

ectospheno an hour ago

I had one in grade school. Taught me the value of backups early in life. Spent all night typing in a game from a magazine. Started it without saving to tape first. It was so loud! Panicked and restarted the machine. Sadness ensued.

Replaced it with a C128-D. Didn’t get my first intel until I bought a 386 after graduating high school. Good times.

hn_acc1 44 minutes ago

Same here - parents bought one for me in 1982, IIRC. By 1984 I had moved to Atari XL, but I'll always have a soft spot for the TI-99/4A, Extended Basic cartridge, speech synthesizer, cassette drive, etc.

My sister and I used to co-type programs from "Compute!". The times were so much simpler then..

icedchai 34 minutes ago

The TI99/4A was my first computer when I was 7 or 8. Unfortunately, no cassette drive. As soon as I shut it off, my basic program was gone!

raddan 20 minutes ago

nonamenoslogan an hour ago

HOLY COW. Thank you for this. I LOVE the Ti99/4a, its one of the first computers I ever used. I've got one up and running at home now currently and can't wait to try this.

raddan 17 minutes ago

Btw, there is a lovely third party replacement for the TI99/4a video chip that lets you output VGA. It’s a major life improvement if you are seriously using it. I Dremeled my case but you can route the ribbon cable to avoid it if you’d prefer not to modify anything. Happy to send you a link if you don’t already know about it.

raphar 21 minutes ago

It's the first computer I ever programmed, I was twelve years old then. <3

haunter an hour ago

This is the main updated comment with the user guide and download

https://forums.atariage.com/topic/380883-unix99-a-unix-like-...

bink 40 minutes ago

Thanks. I wasn't looking forward to browsing all those pages in the hopes of finding the source. Did they never put it up on GitHub?

MBCook an hour ago

Wow. The TI-99 is such a perfect fit for this too given the chip was designed for multi-user computing in a way other home computer chips weren’t.

All due to TI’s desire to use the same chip standards across all their machines big and small, IIRC.

jandrese an hour ago

While the CPU is a better fit than the 8 bit contemporaries, the 16kb of working memory is going to be a struggle.

SoftTalker an hour ago

It's cool because the registers are all in RAM, with a "workspace pointer" on the CPU pointing at where they are. This is slow, but a context switch is just changing that pointer.

jandrese 30 minutes ago

MBCook an hour ago

Yeah it really was an interesting choice on their part. Makes sense as a move for TI. Not the target market.

hunterpayne 38 minutes ago

I learned to program on this exact hardware in the early 80s as a small child. It uses BASIC. It's hard drive was modem tones recorded to an analog audio tape. Its monitor was an analog TV. There was no mouse. The keyboard was built into the computer itself.

UncleOxidant 40 minutes ago

So assuming one wanted to buy a used one of these (I had timex sinclairs around this time) how would one display the composite video nowdays?

jandrese 28 minutes ago

A USB video capture device or a converter box. There are devices sold specifically to interface these old machines with modern displays. One of the more famous ones is the RetroTINK.

glimshe an hour ago

The joy of computing still lives in the age of AI...

buildsjets an hour ago

Does it run PARSEC? Nice shot captain!

b00ty4breakfast an hour ago

made me remember knightOS

https://github.com/KnightOS/KnightOS

Zardoz84 an hour ago

WoW!

bananamogul an hour ago

Imagine a Beowulf cluster of these.