Understanding The Aha-398X Adapter; Multiple Independent Channels - Adaptec AHA-3980 User Manual

Understanding the
AHA-398x Adapter
Adaptec's AHA-398x adapter is a multichannel PCI-to-SCSI RAID
adapter for disk arrays. As a host adapter, the AHA-398x provides
the interface between your computer's PCI bus and your SCSI
drives. As a RAID adapter, the AHA-398x lets you create and oper-
ate arrays of SCSI disks. The AHA-398x has special onboard features
that speed many RAID read and write operations.

Multiple Independent Channels

Each AHA-3980/3980W adapter has two SCSI channels: A and B.
Each AHA-3985/3985W adapter has three channels: A, B, and C.
Each channel functions as an independent RAID adapter.
The AHA-3980 and AHA-3985 are 8-bit adapters. Each channel on
these adapters supports up to seven 8-bit Fast SCSI devices. The
AHA-3980W and AHA-3985W are 16-bit adapters. Each channel on
these adapters supports up to 15 SCSI devices. All 15 devices can be
16-bit, or you can combine 8-bit and 16-bit devices. If you combine
devices, a maximum of seven can be 8-bit devices.
The channels have the following connectors:
Channel A: One internal and one external SCSI connector
Channel B: One internal SCSI connector
Channel C (AHA-3985/3985W only): One internal SCSI
connector
AHA-3980/3980W/3985/3985W User's Guide
Stock Number: 510810-00, Rev. D
Print Spec Number: 493479-00
Current Date: 3/1/99
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ECN Date: 3/19/96