RAID Controller Circuit Boards
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Features of the RAID Controller include:
•Main processor coupled with a companion chip
•Proprietary XOR engine ASIC that provides data processing
XOR function and data cache SDRAM control
•Four 2Gb-capable fibre protocol chips for the device and host
ports
•Dual internal 528 MB/s, 64-bit, 66 MHz PCI buses
•Separate memory areas for processor and user data
•Scalable data cache memory: 128, 256, 512 MB DIMMs
•128 KB NVRAM configuration memory
•Real Time Clock
•4 MB Flash PROM
•Transparent failover/failback with multiple target ID support
The I/O circuit board includes a Battery Backup Unit (BBU)
that maintains memory content in case of AC power failure.
Power for the BBU is provided by a battery pack mounted in
the fan module of the enclosure.
RAID Controller Circuit Boards
This section gives a brief description of the three RAID
controller circuit boards: Controller, I/O, and Ethernet.
Controller Circuit
Board The controller circuit board oversees and regulates the flow
of data from a host through the I/O circuit board to the disk
arrays in the 2Gb SANbloc enclosure. The controller circuit
board performs these operations with a proprietary archi-
tecture, using the following components:
•Main microprocessor and companion chip
•Control-store memory
•Memory Controller/Hardware XOR Engine ASIC (XOR ASIC)
•Flash PROM
•Non-volatile RAM (NVRAM)
•Dual universal asynchronous receiver/transmitter (DUART)
•Fibre Channel I/O processors