One of my ACE1000s has a keyboard with an EPROM. I've desoldered it and read it in; the image is attached.
Note: the original EPROM is an Intel 2758. It appears to be a single-voltage 2708, with a pinout matching the 2716 minus A10 (pin 19). I grounded pin 19 and read it as a 2716, so the resulting ROM dump is doubled. You should be able to burn it to a 2716 as-is, as pin 19 is grounded on the keyboard PCB.
I'm currently trying to fix an old serial terminal (https://www.vcfed.org/forum/forum/t...elcon-ambassador-iv-vcs-204-portable-terminal) and its keyboard looks like a very close cousin of the Ace, with even the same 2758 EPROM (though this one is National Semiconductor) - Does the Ace keyboard also use the General Instrument 19-04592-013 as the controller, or a different variant of the GI 4592?
For some reason I'm not able to read out the contents of my ROM. Telling my TL866-II to read it as a 2816, it never reads the same data twice. I'm trying to just set it up on a breadboard to see one byte at a time, but not having luck with that so far either.