Personal Computer User Manual

RAM500 Memory Expansion Module
http://www.motorola.com/computer/literature D-13
D
*Common GND pins mate to GIGA assemblies with ground plates.
RAM500 Programming Issues
The RAM500 contains no user programmable registers, other than the
Serial Presence Detect (SPD) Data.
Serial Presence Detect (SPD) Data
This register is partially described for the RAM500 within the MVME5100
Single Board Computer Programmer’s Reference Guide. The register is
accessed through the I
2
C interface of the Hawk ASIC on the host board
(MVME5100). The RAM500 SPD is software addressable by a unique
address as follows: The first RAM500 attached to the host board has has
an SPD address of $AA. The second RAM500 attached to the top of the
first RAM500 has an SPD address of $AC.
133 GND SDRAMCLK3 134
135 +3.3V 136
137 SDRAMCLK4 138
139 GND* GND* 140
Table D-4. RAM500 Top Side Connector (J1)
Pin Assignments (Continued)