#More on BAD CHIP RAM
26-Nov-90 00:37:38
Sb: #7069-#More on BAD CHIP RAM
Fm: MicroSearch/Greg White 72230,1617
To: Gregory B. Tibbs 73767,456
Greg, this is Greg 😉
I think what Don was referring to was what is known as the Amazing
Computing Magazine 512K upgrade along with Dave Haynie's auto-config mod.
This consisted of 16 64K x 4 chips piggybacked on the original 8
motherboard memory chips along with some decoding that placed the new
memory at 80000H. Addmem was used to bring the memory online. There was
also a somewhat-kludge using the drive LED to trigger an auto-config
sequence. Later Dave Haynie came out with a 2 chip mod on the daughter
board that relocated the memory to C00000H so that it configured
automagically.
This memory rode on the motherboard chip memory and ran at the same speed
as chip. However since it, of course was not accessible as chip, it came to
known as Half-FAST memory.
Greg (The other one)
Greg White / MicroSearch 72230,1617
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