Hi tony,
>Are there any other markings on them? I remember once seeing some Mostek
>'chips' like these that had 2 off 4164s on top, and were essentially 128K
>bit DRAMs (separate CAS signals to the 2 halves IIRC).
Yes, they are Mostek - and I recall the stacked 4164's in the IBM AT - I just
posted that they were 4116s, but thats due to bad bits in the organic memory
array - you just reminded me that they were 4164's - allowing 512K on the
256K board - ahh the days of such huge capacity...
>I wondef if you've found a 32K bit version made from 2 off 4116s.
It does appear that this is what these things are ...
IIRC, there was a similar stacked arrangement for SRAM chips in the Radio
Shack (Kyocera) Model-100 - the "8k" device was actually 4 x 2k devices on
a small carrier - problem was that they brought out the 4 selects instead
of address lines, so you couldn't just put in an 8k device - I bought a
third party RAM chip which had an 8k device on a small board with some
diodes to generate a common select (the extra address lines must have been
there as well, because there was no other logic on the board) - seemed a
skunkwork design to me, however it never gave me trouble (in fact it's
still working).
What wonderful little things get created to fill in the "gaps" in available
devices...
Regards,
Dave
--
dave04a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
http://www.parse.com/~ddunfield/museum/index.html
Received on Mon Jan 17 2005 - 21:38:59 GMT