PROM Size on a 165

[Peter Gargano]

Ludis Langens wrote:
>
> ...  BTW, the
> ~CS and ~OE signals in a '165 class ECM are swapped from the way they
> are in every other P4 I've checked.

Also, I've seen a 1227808 schematic (ie. a '165 class P4) where J4-14
(EPROM's ~OE) is called ROMDIS, and J14-18 (EPROM's ~CS) is labelled
A15*. 

A15* is a CPU signal generated internally from A15 and E, and possibly
some other CPU signals.

ROMDIS (or ~ROMCS) is simply connected to GND thru' a 10k resistor and
goes to the card edge connector. This arrangement allows the possibility
of retaining the memcal (with EPROM and calibration netres) while the CPU
is executing out of memory connected to the card edge connector.

Peter.
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