Marc; There's probably a HP 2100/21MX singularity being formed in my
basement. I think it's the 7906's that push it over critical mass lol
Hayden - Here is a link to the 21MX M/E/F I/O interfacing guide. It is not
the earlier 2100-specific one that I was thinking about the other day, but
it should be perfectly usable/applicable to the 2100. I'm sure I have both
dead tree versions but the one below will work for you.
www.bitsavers.org/pdf/hp/1000/02109-90006_HP_1000_M_E_F_Series_Computers_IO_
Interfacing_Guide_Sep80.pdf
Best,
J