SCM Firmware

SCM firmware resides on the standard I/O module in flash memory. If the SCM firmware should ever become corrupted or obsolete, you can update it manually using the Loadable Firmware Update Utility. The microprocessor can also communicate with the system power control logic to turn on or turn off power to the rest of the system.

The SCM is powered by an auxiliary 5V supply. You can gain access to the SCM as long as AC power is available to the system (through the wall outlet) and the control panel keyswitch is in the On position. Thus, if the system fails, you can still access the SCM and gather information about the failure.

PSMs, PBMs, and HPMs

The power system managers (PSMs), PCI backplane managers (PBMs), and hierarchical switch power manager (HPM) are the “slaves” of the master SCM. The SCM gathers all environmental data from the slaves. The PSMs, PBMs, and HPM perform the following:

Monitors environmental sensors

Monitors voltages, power supplies, and fans

Shuts down a subsystem (QBB or PCI box) if a fatal condition (temperature reaches a fatal limit or a power failure occurs) is detected

Configuration, Error Log, and Asset Information

The SCM provides additional functionality to read and write configuration and error log information to FRU error log devices. All reading and writing of the FRU EEPROMs is done by the slaves under the direction of the SCM.

Using the System Control Manager 8-5

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Compaq GS320, GS160, GS80 manual SCM Firmware, PSMs, PBMs, and HPMs, Configuration, Error Log, and Asset Information