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/
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.
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/
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/
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/
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?
What are the best games for this #retrocomputers
#ti99_4a
#thomsonto7
#vtech_laser200 and 210
#tandycoco
#sinclairzx81
#msx1
#sharpmz700
#sharpmz800
What would you think?
Hope for some nice ones .. :)
Also new ones ... ;)
I recently attended the Vintage Computer Festival Southwest (VCFSW) at the University of Texas at Dallas campus. This 3-day event was packed with presentations and displays of retro computer and gaming hardware from the early days of computing. Here is a more detailed analysis of the weekend:
https://medium.com/the-ember-project/vintage-computer-festival-vcf-southwest-2025-68351d004434
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/
McMartin
Xavier Ashe 
Harzretro
Tom Gambill