1 Jun
2009
1 Jun
'09
5:50 p.m.
Date: Mon, 1 Jun 2009 06:50:55 -0700
From: dwight elvey <dkelvey at hotmail.com>
Does anyone have a nice pointer to a diagram
of how the 68K bus is to be connected to RAM?
I not that familiar with all the various signals.
I've spent some time searching but maybe don't
have the right search string.
Dwight
Do you want to interface with SRAM or DRAM? DRAM typically has
multiplexed addresses (address sent in two sequential chunks on same
wires) and so you're going to need some kind of memory controller to
handle that plus refresh for the DRAM.
If you're trying to interface with SRAM that typically just takes a
straight address and does not require refresh, so it's much easier. I've
only done it on the 68HC11 so your app may be different, but it is usually
discussed in the part's User's Guide, so you should download that from
Motorola if you have not already. Oh, and check for any relevant white
papers on the topic as well (AKA Application Notes).
Jeff Walther