Sun Microsystems Netra T4 AC100, Service And System Reference Manual

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10-22 Netra T4 AC100/DC100 Service and System Reference Manual • August 2001
The I2C multimaster bus interfaces with the following devices:
■
System configuration card reader (SCCR)
■
FC-AL backplane
■
Power distribution board (PDB)
■
Lights Out Management board
■
LED and switch board
■
Power Supply Unit
The I2C bus supports a Lights Out Management (LOMlite2) board through the I2C
connector to the PDB. The LOMlite 2 board is a remote support feature that provides
remote monitoring and system administration.
The LOMlite2 board is powered by a 5 V standby supply that enables the board to
remain powered after the host has shut down.
10.2.7 PCI Bus
The peripheral component interconnect (PCI) bus is a 32-bit or 64-bit bus with
multiplexed address and data lines. The PCI bus provides electrical interconnect
between highly integrated peripheral controller components, peripheral add-on
devices, and the processor/memory system.
There are two PCI buses in the Netra T4 system:
■
One-slot, 3.3 VDC, 64-bit or 32-bit, 66 MHz or 33 MHz bus
■
Three-slot, 5.0 VDC, 64-bit or 32-bit, 33 MHz bus
Both buses are controlled by the SBC ASIC. There are two on-board PCI devices, the
SCSI controller and the PCIO-2 ASIC, on the 33 MHz PCI bus. The ISP2200A FC-AL
disk controller is located on the 64-bit, 66 MHz PCI bus.
10.2.7.1 PCI Cards
PCI cards come in a variety of configurations. Not all cards fit or operate in all PCI
slots, so it is important to know the specifications of your PCI cards and the types of
cards supported by each PCI slot in the system.
Some PCI cards are as short as 174.6 mm (6.88 in.) in length—called short
cards—while the maximum length of PCI cards is 311.9 mm (12.28 in.)—called long
cards. Slots 0, 1 and 2 in the Netra T4 system can accommodate either a long or a
short card, but slot 3 is restricted by the FC-AL drive assembly and can
accommodate only a short card.
Older PCI cards communicate over 32-bit PCI buses, while many newer cards
communicate over wider 64-bit buses.