There is an ap note that came with the Parallax(now Tech Tools) programmer
on interfacing dynamic ram.  You should be able to get it off one of teir
web sites.

Greg Brault wrote:

> Hi all,
>
> Has anybody played around with dynamic RAM and refreshing it?  I know
> you have to refresh it about every 2 milliseconds, and I was thinking I
> might be able to do it with a PIC or something.  If anybody has any
> experience with this, I'd like to hear from ya.  Thanks!
>
> Greg
> gjbrault@mtu.edu