Xycom XVME-653, Manual

Page: 79 / 113

Appendix A – DRAM Installation
A-1
Appendix A – DRAM Installation
The XVME-653/658 has two 72-pin single inline memory module (SIMM) sites in which
memory is inserted. Due to the CPU speed, DRAM access time should be 70 ns or less,
and must be 60 ns to run with the zero wait states.
The XVME-653/658 supports 32, 64, 128, and 256 MB of DRAM. You can use 4Mx32,
8Mx32, 16Mx32 DRAM SIMM, and 32Mx32 DRAM SIMM sizes. Table A-1 lists the
combinations needed for the memory configurations. (The U number is silkscreened on
the front of the board.)
Table A-1 DRAM SIMM Combinations
Memory SIMM Site U34 SIMM Site U35
32 MB 4M x 32 4M x 32
64 MB 8M x 32 8M x 32
128 MB 16M x 32 16M x 32
256 MB 32M x 32 32M x 32
Figure A-1 illustrates DRAM installation.