HP 2100S microcode blanks?

[Jay West]

Does anyone have any documentation saying what parts were acceptable for 
microprograming on the 2100S? I can't seem to locate that information.

I have some sample parts (preprogrammed), but they only have HP specific 
part numbers, and ascending Motorola numbers, so I'm pretty sure those don't 
refer to the blank part only the programmed one; other than Motorola being 
the Mfg.

All I know at this point is they are motorola 4bit X 256 parts. I would 
think some of the 2100S microprogramming books would state this but so far 
my search has come up empty. If anyone knows... let me know!

Jay West