User's Manual

1-2 Overview

1.1 Features

MegaRAID SCSI 320-0 features include:

· Provides a high performance I/O migration path while preserving

existing PCI-SCSI software.

· Performs SCSI data transfers up to 320 Mbytes/s.

· Performs synchronous operation on a wide low-voltage differential

(LVD) SCSI bus.

· Allows up to 15 LVD SCSI devices on the wide bus.

· Includes an Intel GC80302 integrated I/O processor that performs

RAID calculations and routing.

· Supports 32 to 128 Mbytes of SDRAM on-board cache memory used

for read and write-back caching, and RAID 5 parity generation.

1.2 NVRAM and Flash ROM

A 32 Kbyte x 8 nonvolatile random access memory (NVRAM) stores

RAID system configuration information. The MegaRAID SCSI 320-0

firmware is stored in flash ROM for easy upgrade.

1.3 Single-Ended and Differential SCSI Buses

The SCSI standard defines two electrical buses:

· Single-ended bus

· Low-voltage differential bus