Re: Request a discrete refresh circuit schematic

["PZ" <skierpaul@yahoo.com>]

Duh Bill, anyone with a datasheet can figure that out.

With most 72 pin SIMMs you can access the two 16 bit words
individually.  You cant, in most cases, individually access every byte
however.  About 3 years ago I had a 4MB GS ramcard proto that worked
just fine with an 8mb 72pin SIMM.  I'll have to dig around and find
whats left of it.

- Paul

Bill Garber wrote:
> "PZ" <skierpaul@yahoo.com> wrote in message
> 1158421294.113916.278170@e3g2000cwe.googlegroups.com">news:1158421294.113916.278170@e3g2000cwe.googlegroups.com...
> : 72 pin simms would be more difficult since we only have an 8 bit data
> : bus and 72 pin simms expect a minimum dbus of 16 bits.  I'm not saying
> : you can't do it, there's a couple ways to implement 72 pin simms on an
> : 8 bit bus, but it'll require some extra logic over the 30pin simms.
> :
> : - Paul
>
>
> Paul,
>
> 72 pin simms are 32 bit, DQ0-DQ31.
> Although you can use more than 8 bits
> on the data buss of the simm, there
> isn't an easy method for guarateeing
> that you collect back the same data
> that you put on it.
>
> Bill Garber
> Owner - Garberstreet Enterprizez
> Co-owner - GSE-Reactive.com
> (610)935-7676 (610)329-8996