13 Sep
1999
13 Sep
'99
5:19 p.m.
I wrote:
Actually, RAM chips were usually only 1818 if there
was some unique
characteristic, such as a hard-wired address decode. General-purpose
RAM chips were usually 1820.
Tony says:
1818-0156 = 4K 22 pin standard DRAM
1818-0701 = 6810 128 byte SRAM
...
AFAIK, all of those are standard parts, not
custom-modified for HP. Or at
least I've replaced some of them with the equivalents and the device
worked afterwards :-)
PALs/HALs generally have 1820-numbers, though...
Oops, other way around.