1 Introduction



The SBus Expansion Subsystem (SES) Board provides SBus expansion slots for SPARCsystems 670MP and SPARCservers 690MP. Up to two expansion subsystems can be added to a host server. Each subsystem consists of an SES Board with four SBus slots that are connected to a mother board via a cable and an SES Adapter Card.

1.1 Subsystem Components

The main components of the SES Board are as follows (Refer to Figure 1-1):

    Figure 1-1 Subsystem Components

Figure 1-2 shows the SBus Expansion Subsystem connected to the system board in a SPARCsystem or SPARCserver.

    Figure 1-2 SES Board Connected to a System Board

1.2 Subsystem Description

Functional Description

The SBus expansion adapter card is installed in one of the SBus slots of the SPARCsystem or SPARCserver (located on the system board). This adapter card transmits SBus-related information to the SBus expansion board which is inserted into a slot in the cardcage of the SPARCsystem or SPARCserver. One SBus expansion adapter card must be installed for each SES Board.

The SBus expansion cable is a shielded round cable. It connects to the SBus adapter card in the SPARCsystem or SPARCserver and to the 96-pin connector on the expansion board which is contained in the host cardcage.

Software Requirements

The software for the SES Board consists of:

1.3 Tools Required

1.4 Field-Replaceable Units (FRUs)

Table 1-1 is a list of the Field Replaceable Units (FRU) and their part numbers.

    Table 1-1 Field-Replaceable Units 

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Part Description      Part Number
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SES Board             F501-1955-xx
                      
Cable, 96 pin, (.8m)  F530-1896-xx
                      
SES adapter card      F501-1840-xx

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1.5 Related Documentation

1.6 Electrostatic Discharge Precautions

Caution - Circuit board components are vulnerable to damage by electrostatic discharge (ESD). An electrostatic charge can build up on the human body and then discharge when you touch a board. Such discharge can be produced by walking across a carpet and touching a board, or by other similar causes. Before handling any board, make sure you dissipate your body's charge. Touch a conductive surface of the chassis or other element connected to common earth ground to discharge the static electricity present in your body. To minimize risk of ESD damage:
o Handle board by edges only.
o Store board in antistatic bag provided.

Use Sun ESD kit P/N 250-1088 (or equivalent) when working on the 600MP system Board or the 600MP expansion memory board. Sun ESD kit P/N 250- 1088 contains the Sun approved Sun ESD mat which has 0.25" of cushioning to protect underside components, prevent board flexing, and provide ESD protection. Instructions for use are printed on the mat.

Do not use ESD kit P/N 560-1302 when installing SPARCsystem 600MP boards. ESD kit P/N 560-1302 does not provide adequate protection for