Pci Bridge/Cpu; Cache Memory - Dell PowerEdge Expandable RAID Controller 3 User Manual

Ta b l e 6 - 7 . P E R C 3 / Q C S p e c i f i c a t i o n s (continued)
Parameter
Operating voltage
SCSI controller
SCSI data transfer rate
SCSI bus
SCSI termination
Termination disable
Devices per SCSI channel
SCSI device types
RAID levels supported
SCSI connectors
Serial port

PCI Bridge/CPU

PERC 3/QC uses the Intel i960RN PCI bridge with an embedded i960RN
RISC processor running at 100 MHz. The RN bridge handles data transfers
between the primary (host) PCI bus, the secondary PCI bus, cache memory,
and the SCSI bus. The DMA controller supports chaining and unaligned
data transfers. The embedded i960JN CPU directs all controller functions,
including command processing, SCSI bus transfers, RAID processing, drive
rebuilding, cache management, and error recovery.

Cache Memory

128 MB of PERC 3/QC cache memory resides in a memory bank that uses a
64 MB or 128 MB SDRAM DIMM. PERC 3/QC supports write-through or
write-back caching, selectable for each logical drive. To improve
performance in sequential disk accesses, the PERC 3/QC controller uses
read-ahead caching by default. You can disable read-ahead caching.
Specification
5 V, 3.3 V
Four SCSI controllers for 160M and Wide
support.
Up to 160 MB/s per channel
LVD or single-ended
Active
Automatic through cable and device detection
Up to 15 wide or seven narrow SCSI devices.
Synchronous or asynchronous.
0, 1, 5, 10, and 50
Two 68-pin internal high-density connectors for
16-bit SCSI devices. Four ultra-high density 68-
pin external connectors for 160M and Wide
SCSI.
9-pin RS232C-compatible connector (for
manufacturing use only)
PE RC 3/QC Fe atures
79