30 Aug
2007
30 Aug
'07
12:32 a.m.
Dave Dunfield schrieb:
Btw, for an ultra-simple EPROM emulator, use one of
the
Dallas NVRAM chips (DS1225 (8K) , DS1235 (32K) etc.).
Stuff it in a RAM socket of a convienent SBC to program
it, and make an adapter by piggybacking a couple of sockets
and moving the necessary address lines, mask write etc.
to plug it into a ROM socket.
Alternative to that is the use of TIMEKEEPER (48Txx) or ZEROPOWER RAMs
(48Zxx)
which are rather expensive when you hunt for them in the obvious places,
but I got lots of them
from old Sun IPC/IPX machines before they were thrown
out here. Capacity
is typically 2Kx8 or 8Kx8 for these devices, newer ones also have
32K or
128K.
The timekeeper versions also provide a hardware clock which is useful
once in a while.
Regards
--
Holger