SCSI Hardware Support

SCSI Hardware Support

The Silicon Graphics computer systems supported by IRIX 6.2 can attach multiple SCSI adapters, as follows:

The Indy workstation has at least one SCSI adapter on its motherboard, and can have up to two additional adapters on a GIO option board.
The Indigo2 series supports two SCSI adapters on the motherboard.
The Challenge S system has two SCSI adapters on the motherboard, and can have one or two additional on each of one or two additional GIO option boards, for a maximum of sixadapters.
The Challenge M system supports one SCSI adapter on the CPU board and can have up to two additional adapters on a GIO option board.
The POWERchannel (IO3) boards used in the Crimson line support two SCSI adapters per board.
The Power Channel-2(TM) (IO4) boards used in the Challenge and Onyx series support two SCSI adapters, plus many as six additional SCSI adapters on mezzanine cards, for a maximum of eight adapters per IO4. In addition, VME-SCSI adapters (Jag units) can be installed on the VME bus in these systems.

In all systems, DMA mapping hardware allows a SCSI adapter to treat discontiguous memory locations as if they were a contiguous buffer, providing scatter/gather support.