Sram Access - Performance Computer PT-VME161 User Manual

Performance Computer
As an alternative to the memory sizing algorithms required by the 151, the 151A System Status Register
2 provides DRAM size information. See "System Status Register 3" on page 66 for list of the encoded
values.

SRAM Access

The PT-VME151A does not support the SRAM option that was available on the 151. As a result the
SRSZ field in System Status Register 1 will always return 0, indicating that NO SRAM is installed.
On the 151 accesses to address space allocated to the SRAM would never generate a Bus Error. Accesses
to the same space on the PT-VME151A will terminate with a local Bus Error. PT-VME151 software that
is intended to run on the PT-VME151A should be checked for references to this space.
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