21 Dec
2015
21 Dec
'15
9 a.m.
DEC documentation differs on the location of the two
uROM's in the
LSI-11/2 (KD11-HA, M7270): the 'Microcomputer Products Handbook' gives
the order (from the handle end) as KEV11, uROM 1, uROM 0, Control, Data
Path ...
From which I conclude that either: i) one of the documents, perhaps the
Handbook, is wrong, or ii) the 'Control' chip must also be a uROM, and
that there is some variation in how the 3 chips can be plugged in?
Anyone know what's up here?
To answer my own post, I looked at the prints (should have done this before I
posted, sigh), and there is no way it can be ii). The Control chip has a
bunch of discrete signals on pins where the uROM's have micro-instruction bus
pins. So there's no way you can swap them around.
So the 'Microcomputer Products Handbook' diagram (pg. C-18) has to be wrong.
Noel