Compaq AlphaServer ES40, Service Manual

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System Overview 1-21
Dual-Port RAM (DPR)
The ES40 system features a dual-port RAM—RAM that is shared between the
RMC and the system motherboard logic—to ease communication between the
system and the RMC. This book refers to the dual-port RAM as the DPR.
The RMC reads 256 bytes of data from each FRU EEPROM at power-up and
stores it in the DPR. This data contains configuration and possibly error log
information. The data is accessible via the TIG chip to the firmware for
configuration information during start-up. Remote or local applications can read
the error log and configuration information. The error log information is
written to the DPR by Compaq Analyze (see Chapter 5) and then written back
to the EEPROMs by the RMC. This ensures that the error log is available on a
FRU after power has been lost.
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Section 1.10.1 describes the SPC logic.
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Section 1.10.2 describes the RMC logic.