#ti99_4a — Public Fediverse posts

This week on the blog: I wrap up playing with my game board rendering by trying out various ways I could make it render on the TMS9918A chip. We get a lot of options without needing a lot of tricks!

https://bumbershootsoft.wordpress.com/2026/03/07/designing-a-game-board-for-the-tms9918a/

#retrocomputing #colecovision #ti99_4a #msx

I'm expecting to shift focus on the blog for a bit to "various kinds of shenanigans you can get up to with various sprite systems" and that also means making occasional mockups and illustrations.

I'm very happy with how this one came out, and will be cheerfully filing it away until I come back to the TMS9918.

#retrocomputing #ti99_4a #coleco

This week on the blog: wrapping up this pass at TI-99/4A by trying to use the CPU in more traditional ways, or under more traditional system designs like having 32KB of RAM instead of 256 bytes. The TMS9900 CPU is so odd that call stacks still aren't necessarily the answer!

https://bumbershootsoft.wordpress.com/2026/01/31/ti-99-4a-revisiting-implementation-strategies/

#retrocomputing #ti99_4a

@cR0w Hey, that's a TI-99/4A ! That was my first computer.
#TI99_4a #ti #TI99

New on the blog: Continuing TI-99/4A experiments, this time mixing native code with the on-console bytecode system.

https://bumbershootsoft.wordpress.com/2026/01/24/ti-99-4a-hybrid-software-development/

#retrocomputing #ti99_4a

This week on the blog: I go close some gaps in my understanding of the capabilities offered by the TI-99/4A's firmware. Now that I've picked up a working knowledge of most of the underlying hardware, on the system itself and its successors, I can see a bit more clearly.

https://bumbershootsoft.wordpress.com/2026/01/17/ti-99-4a-leaning-more-heavily-on-the-firmware/

#retrocomputing #ti99_4a

I've been playing around a bit with TMS9900 programming again over the holiday and trying to do a bit more with it, tracking the retro systems I normally use, and...

... am I correctly understanding that this has a carry bit, but never actually looks at it except via JOC/JNC? It's one thing to not have a 9- or 17-bit rotation operation, but it looks like even doing a multiprecision ADD requires me to carry the 1 by hand.

Am I missing something?

#retrocomputing #ti99_4a

This week: Wrapping up the TI-99/4A series with a careful code walkthrough of a full port of my shooting gallery Rosetta-stone program.

https://bumbershootsoft.wordpress.com/2025/03/08/ti-99-4a-a-detailed-code-walkthrough/

#retrocomputing #ti99_4a

New on the blog: My three articles on the TI-99/4A have turned into five. This is the fourth, looking over all the stock hardware I didn't mess with last week and putting some real thought into how you organize "real" software on a 16KB system where the CPU proper can only see 64-256 bytes of it.

Next week I take the biggest test program I made for this and walk through the design step by step.

https://bumbershootsoft.wordpress.com/2025/03/01/ti-99-4a-finishing-our-preparations/

#retrocomputing #ti99_4a

New on the blog: writing some machine code (and some not-quite-machine code) on the TI-99/4A. Getting just enough of a handle on the system that it's possible to start plotting out projects of meaningful size.

https://bumbershootsoft.wordpress.com/2025/02/22/writing-cartridge-software-for-the-ti-99-4a/

#retrocomputing #ti99_4a

This week on the blog: playing with a retro platform I had only brief experience with as a kid: the TI-99/4A. It was *deeply* wacky, left an easily detectable footprint despite sinking without a trace, and a bunch of its components helped define game-friendly home-computing worldwide for a decade.

This week I'm releasing the platform guide, making its BASIC do things, and next week we'll see why BASIC was the only real option for us as kids.

https://bumbershootsoft.wordpress.com/2025/02/15/the-8-bit-eras-weird-uncle-the-ti-99-4a/

#retrocomputing #ti99_4a

Today we have some new high-quality scans for the TI-99/4A:

- Large-format Schematics of the TI-99/4A, Expansion Box and cards
- various manuals and addendum.
- TI-99/4A console and peripheralexpansion system - technical data

- https://archive.org/details/ti-99-4-a-schematics
- https://archive.org/details/ti-99-4-a-disk-drive-memory-system-php-1240-manual-1039345-2
- https://archive.org/details/ti-99-4-a-console-and-peripheralexpansion-system-technical-data

#retrocomputing #retro #ti99 #ti99_4a

Call Me Alpiner

https://youtu.be/uq-gYOrU8bA?si=bnVo0MmsaYhYet3U

#RetroVideoGameASong
#HashtagGames
#PaulSimon
#TI99_4A