Motorola MVME177P, Installation And Use Manual

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Preparing the Board
http://www.motorola.com/computer/literature 1-9
1
Petra SDRAM Size (S3)
MVME177P boards use SDRAM (Synchronous DRAM) in place of
DRAM. For compatibility with user applications, the MVME177P’s
SDRAM is configurable to emulate 4MB, 8MB, 16MB, 32MB, 64MB, or
128MB ECC-protected DRAM. Board configuration is a function of
switch settings and resistor population options.
S3 is a four-segment slide switch whose lower three segments establish the
size of the ECC DRAM memory model (segment 4 is not used.) Refer to
the illustration and table below for specifics.
.
Table 1-3. Petra SDRAM Size Settings
S3
Segment 1
S3
Segment 2
S3
Segment 3
MCECC
DRAM Size
ON ON ON 4MB
ON ON OFF 8MB
ON OFF ON 16MB
ON OFF OFF 32MB
OFF ON ON 64MB
OFF ON OFF 128MB
2734 0004
ON OFF
32MB
(typical configuration)
4
1
PETRA SDRAM SIZE
S3