I/O+ Boards

Several types of I/O+ boards are available: SBus+ I/O board, Graphics+ I/O board, and PCI+ I/O board.

Board slot 1 requires an I/O+ board because this is the only slot that connects with the internal media tray. If slot 1 does not contain an I/O+ board, the drives in the media tray will not function.

All empty card cage slots must contain a filler panel.

SBus+ I/O Board

The SBus+ I/O board with 100 MB/sec Fibre Channel (see Figure B-6) includes two SYSIO ASICs that provide two SBuses:

• One for two plug-in SBus cards and two GBIC (100 MB/sec Fibre Channel) interfaces

• One for one plug-in SBus card and the onboard devices (10/100 Mbit TPE and Single-ended Fast/Wide SCSI)

SBus connector slots 1 and 2 on the SBus+ I/O board can accommodate a double-wide SBus card.

Figure B-6 SBus+ I/O Board

Graphics+ I/O Board

The Graphics+ I/O board with 100 MB/sec Fibre Channel (see Figure B-7) includes one SYSIO ASIC that provides a single SBus for two plug-in SBus cards, two GBIC (100 MB/sec Fibre Channel) interfaces, and the onboard devices (10/100 Mbit TPE and Single-ended Fast/Wide SCSI).

Figure B-7 Graphics+ I/O Board

PCI+ I/O Board

The PCI+ I/O board (see Figure B-8) has two PCI bus connectors:

• Each connector can accommodate a PCI riser card

• Each riser card accommodates one PCI short card

In addition, onboard devices on the PCI+ I/O board provide Fast Ethernet (10/100 Mbit) and Fast Wide SCSI interfacing.

Figure B-8 PCI+ I/O Board

The board contains five subsystems: IO(PCI Bus), Memory, Bus Interface, FireHose Interface, and Clock Generation. Four of these subsystems: the IO(PCI Bus), Memory, Bus Interface and internal board interface subsystems include ASICs. The Clock subsystem distributes and generate clocks for the ASICs and PCI Bus Interfaces on the board.