Personal Computer User Manual

RAM500 Memory Expansion Module
http://www.motorola.com/computer/literature D-5
D
SROM
The RAM500 memory expansion module contains a single 3.3V, 256 x 8,
Serial EEPROM device (AT24C02). The Serial EEPROM provides Serial
Presence Detect (SPD) storage of the module memory subsystem
configuration. The RAM500 SPD is software addressable by a unique
address as follows: The first RAM500 attached to the host board has its
SPD addressable at $AA. The second RAM500 attached to the host board
has its SPD addressable at $AC. This dynamic address relocation of the
RAM500 SPD shall be done using the bottom-side connector signal
A1_SPD and A0_SPD.
Host Clock Logic
The host board provides four SDRAM clocks to the memory expansion
connector. The frequency of the RAM500 CLKS is the same as the host
board.
RAM500 Module Installation
One or more RAM500 memory expansion modules can be mounted on top
of the MVME5100 for additional memory capacity. To upgrade or install
a RAM500 module, refer to Figure D-2 and proceed as follows:
1. Attach an ESD strap to your wrist. Attach the other end of the ESD
strap to the chassis as a ground. The ESD strap must be secured to
your wrist and to ground throughout the procedure.
2. Perform an operating system shutdown. Turn the AC or DC power
off and remove the AC cord or DC power lines from the system.
Remove the chassis or system cover(s) as necessary for access to the
CompactPCI boards.
3. Carefully remove the MVME5100 from its VME card slot and lay
it flat, with connectors P1 and P2 facing you.
4. Inspect the RAM500 module that is being installed on the
MVME5100 host board (bottom configuration if two are being
installed, top configuration if only one is being installed) to ensure