First post, by pentiumspeed
I'm working on a project using a 4MB 72pin SIMM wired into kingston KTC-x000 (4MB or 1MB) memory expansion card as 1MB x 1bit DIP ICs is impossible to find at any price in quantity.
Layout of wiring of this memory expansion card conforms to 72 pin signal design! for 4MB, two RAS used (to tie together 2 banks of 8 bits plus parity bit).
Yet the four CAS lines are for 9 bit each bank which is 8 bit plus parity each at a time for total of four CAS lines needed to make 32 bits plus 4 parity bits for 386DX.
Yet the all the address lines are all tied together for all.
What is the reason to separate out four CAS lines while RAS lines are two for up to 4MB layout?
Cheers,
Great Northern aka Canada.