31 Oct
2002
31 Oct
'02
3:55 p.m.
I just realized that my reply to Jerome's inquiry about the
LSI-11 module with five chips was probably wrong. IIRC, the
LSI-11 chip set consists of the control chip, data chip, and
two MICROMs for the base instruction set. The EIS/FIS (KEV11)
is a single additional MICROM. So the original quad-height
LSI-11 module would have four 40-pin chips without the EIS/FIS,
or five with.
Was it the LSI-11/2 half-height module that sometimes used
a hybrid with two MICROMs? If so, it was probably the two
microms that implemented the standard instruction set, in
order to leave a socket open for the KEV11.
On the 11/23 and 11/24, some of the chips were also on dual-chip
hybrids.
Eric