I have often thought about adding 9938 emulation to js99er.net, but as far as I know we don't have any Ti-99/4A software to test the various graphics modes, except for 80 columns text mode.
Here's the Mandlebrot code that was given to me for testing the 9938 support. It (and the code that ran it) was provided to me by Roland Meier back when Classic99 was Ami99, as he used it for a Linux port.
At the time (98-99 timeframe), I couldn't support the Linux side nor the VDP side, so as we fell out of touch the code faded until eventually I dropped it, and stashed it away for later reference.
I haven't run it for a really long time, so I can't help much with doing so.
Edited by Tursi, Sun Mar 4, 2018 3:00 PM.