4 Apr
2003
4 Apr
'03
10:39 a.m.
Hi
I guess the next question is, does anyone have the
dumps of these chips or what the new mapping is??
I have dumps of all the programmed chips in my Z90...
I suspect that there is some remapping of the memory
and some for the I/O. I don't know why it would take
3 chips though. I'll have to dig through my stuff to
AFAIK, the 3 chips involved are the monitor ROM (Z80 code), the memory
mapping PROM and the I/O mapping PROM.
>2) Connect a jumper from the middle pin of U503 to
pin 17 of P509
I believe that's the mod I mentioned which connects an output port line
to the input on the memory mapping PROM, thus allowing software selection
of HDOS (ROM at location 0) or CP/M (RAM at location 0) memory maps.
-tony