Sun Microsystems SPARCstation 4, Service Manual

Page: 148 / 190

11-30 SPARCstation 4/Xterminal 1 Service Manual • January 1995
4. Take the following components that you removed from the defective system board
and install them on the new system board in the following order:
a. NVRAM
See Section 11.6.2 “Replacing the NVRAM Chip.”
b. DSIMMs
See Section 11.3.2 “Replacing the DSIMM.”
c. VSIMM
See Section 11.4.2 “Replacing the VSIMM.”
d. Audio Module
See Section 11.2.2 “Replacing the Audio Module.”
e. SBus card
See Section 11.1.2 “Replacing the SBus Card.”
5. Detach the wrist strap and replace the cover.
See Chapter 7.
6. Power on the system.
See Section 6.2 “Powering On the System.”
11.5.3 Setting Jumpers
Note – This section applies to SPARCstation 4 systems only.
There are two serial port jumpers on the system board. The jumpers are factory-set
to RS423 mode (position A in
FIGURE 11-32
). The ports can be reset to RS232 mode
(position B) for connection to an X.25 network in Europe or Australia.
To change the jumper settings from RS423 mode to RS232 mode:
1. Shut down and power off the system.
See Section 6.1 “Powering Off the System.”
2. Remove the cover and attach a wrist strap.
See Chapter 7.
3. If an SBus card is installed, remove it.
See Section 11.1.1 “Removing the SBus Card.”