Compaq StorageWorks UltraSCSI RAID Enclosure (DS-BA370 Series) User's Guide (EK-BA370-UG. C02, September 1998)

Environmental Monitoring Unit
3–4 UltraSCSI RAID Enclosure
I/O Module Status
The EMU verifies that the six I/O modules are present, properly
installed, and communicating with the backplane, and that
TERMPOWER is at the correct level. The EMU reports an error
condition whenever any one of these conditions are not met. The
EMU also reports the I/O module type to the array controller. If the
controller determines that all modules are not the same type, it
displays this information on the optional maintenance terminal, if
connected.
An integrated circuit on each I/O module functions as a
bus
expander
. The EMU and the array controller can either enable or
disable this circuit on an individual I/O module, thereby controlling
individual external SCSI buses.
Enclosure Configuration Information
The EMU maintains the following configuration information:
• Enclosure number (the PVA SCSI ID switch setting)
• EMU microcode revision
• EMU message protocol revision
• Temperature sensor set points
• Number of installed power supplies by location
• Number of installed disk drive SBBs by location
• Number of operational blowers in each drive SBB shelf bank
• Number and type of I/O modules installed