SCSI Controller

The SCSI version of the server board includes an embedded AdaptecAIC-7899W controller providing dual Ultra160 Low Voltage Differential (LVD) SCSI channels.

The SCSI bus is terminated on the server board with active terminators that cannot be disabled. The onboard device must always be at one end of the bus. The device at the other end of the cable must also be terminated. LVD devices generally do not have termination built-in and need to have a termination source provided. Non-LVDs devices generally are terminated through a jumper or resistor pack on the device itself.

ATA-100 Controller

The ATA version of the server board provides an embedded dual channel ATA-100 bus through the use of the Promise TechnologyPDC20277 ATA-100 controller. The controller contains two independent ATA-100 channels that share a single 32-bit, 33-MHz PCI bus master interface as a multifunction device. The controller supports:

DMA and PIO IDE drives and ATAPI devices

ATA and ATAPI proposal PIO Mode 0, 1, 2, 3, 4; DMA Mode 0, 1, 2; and Ultra DMA Mode 0, 1, 2, 3, 4, 5

IDE transfer rates up to 100 MB/sec per channel

Host interface complies with PCI Local Bus Specification Revision 2.2

IDE RAID

The ATA-100 controller supports IDE RAID through both ATA-100 channels. In a RAID configuration, multiple IDE hard drives are placed into one or more arrays of disks. Each array is seen as an independent disk, though the array may include one, two, three, or four drives. The IDE RAID can be configured as follows:

RAID 0: Striping one to four drives

RAID 1: Mirroring two drives

RAID 1 +: Spare drive (three drives)

RAID 0 +: One to four drives are required

RAID 0 configurations are used for high performance applications, as it doubles the sustained transfer rate of its drives. RAID 1 configurations are primarily used for data protection. It creates an identical drive backup to a secondary drive. Whenever a disk write is performed, the controller sends data simultaneously to a second drive located on a different data channel. With 4 drives attached to dual ATA-100 channels, two striped drive pairs can mirror each other (RAID 0+1) for storage capacity and data redundancy.

Description

11

Page 11
Image 11
Intel SE7500WV2 manual Scsi Controller, ATA-100 Controller