Someone asked about the simm72 stuff, I've Lost the original post.
Below is the brief spec. of a samsung simm72 module which might be
helpful.  You might want to look up the spec. of the module that you
are using because they would have different access time as well data
organization.  The place to look for the information would be the
manufacturer's sites.

Techref has some info on interfacing to simm30 DRAM, it might be a
faster track for you.

If you want the pdf files of the below text and some other
informaiton, email me offlist and I would forward them to you.

Cheers, ling SM

DRAM MODULE M53611601CE0/CJ0-C
M53611601CE0/CJ0 Fast Page Mode
16M x 36 DRAM SIMM Using 16Mx4 & 16Mx1, 4K Refresh, 5V
The Samsung M53611601CE0/CJ0-C is a 16Mx36bits
Dynamic RAM high density memory module. The Samsung
M53611601CE0/CJ0-C consists of eight CMOS 16Mx4bits
DRAMs and four CMOS 16Mx1bit DRAMs in SOJ packages
mounted on a 72-pin glass-epoxy substrate. A 0.1 or 0.22uF
decoupling capacitor is mounted on the printed circuit board
for each DRAM. The M53611601CE0/CJ0-C is a Single In-line
Memory Module with edge connections and is intended
for mounting into 72 pin edge connector sockets.
=95 Part Identification
- M53611601CE0-C(4K cycles/64ms Ref, SOJ, Solder)
- M53611601CJ0-C(4K cycles/64ms Ref, SOJ, Gold)
=95 Fast Page Mode Operation
=95 CAS-before-RAS & Hidden Refresh capability
=95 RAS-only refresh capability
=95 TTL compatible inputs and outputs
=95 Single +5V=B110% power supply
=95 JEDEC standard PDpin & pinout
=95 PCB : Height(1250mil), double sided component

GENERAL DESCRIPTION FEATURES
PERFORMANCE RANGE
Speed tRAC tCAC tRC tPC
-C50 50ns 13ns 90ns 35ns
-C60 60ns 15ns 110ns 40ns

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