First Virtual Communications Voyager 3000 - Manual (Page 35)

Environmental Monitoring Unit
3-1
Chapter Three
EMU
Environmental Monitoring Unit Configurations
Introduction
The Environmental Monitoring Unit ( EMU ) is a multifunction plug-in daughter card that
allows a user to monitor the operational status of a Voyager 3000 system. There is one EMU
per storage shelf. The module provides visual and audible feedback of events to the user. In
addition the EMU provides addressable memory locations which may be read or written to.
This allows more comprehensive monitoring and reporting to intelligent agents such as
Eurologic’s Vision software. The EMU specification is based on the SAFTE ( SCSI Accessed
Fault Tolerant Enclosures ) specification, and contains many of the features detailed there.
EMU Features
•
Monitors presence and status of Fans and Power Supply Units ( PSU ) .
•
Monitors presence of SCSI devices.
•
Monitor UPS status and presence.
•
Indicates error conditions visually and audibly.
•
Adjustable over-temperature warning.
•
Stores insertion counts for all removable devices - PSU, Fan or SCSI Device
•
Communication via serial RS232 port or via I
2
C bus.
•
Fully compatible with Eurologic’s Vision software.
The EMU is a flexible unit which may be configured in a variety of ways. It connects to a host
system via an RS-232 link. Up to eight EMUs may be cascaded together in a Master/Slave
configuration. Each EMU is set up to have a distinct ID. A device having an ID of 0 will be a
Master, all other devices are designated as Slaves. Multiple EMUs are daisy chained together
via an I
2
C bus.
The EMU stores data in a non-volatile EEPROM memory so it is possible to track changes in
the system even if power has been removed. On power up the EMU compares the physical
system configuration to that stored in memory and notes any changes. These changes will be
reported to the Host. It is the responsibility of the Host to process this information.