Hi,
We (PVM) have just released a demo for the PCjr (works even on the 64K-RAM only version[*]):
video: https://www.youtube.com/watch?v=uakDpJns9LA
(thanks monzamess for the capture).
Binary download:
http://pungas.space/pvm-64ko.zip (only run on real hardware, no emulators)
source code here:
https://gitlab.com/ricardoquesada/pcjr-flashparty-2018
and here is high-level documentation that explains how the different tricks were done:
https://retro.moe/2018/09/26/64k-ram-ou ... -the-pcjr/
I hope you like it.
[*]: there is bug displaying 32k RAM video modes when the PCjr has only 64k RAM.