I bought 2 of these (by
https://retro.7-bit.pl/) to use external USB keyboards with case-based 1200s and none of the 6 keyboards I have tested work (4 are made by Rii -- mechanical Blue switches, one is an unbranded from the CheckMate A1500 website, and one is an old Dell).
None work, even after flashing the only firmware update on the retro.7-bit.pl web site.
The company has
no listed working keyboards,
nor will provide me with any such list; they say the keyboards I am using draw too much power (?).
Does anyone have a working keyboard connected to a SUM 1200 device they can suggest?