Sun Microsystems 60 用户手册

C-46

Sun Ultra 60 Service Manual • August 2001

C.4.1

Serial Port Jumpers

Serial port jumpers J2604 and J2605 can be set to either RS-423 or RS-232 serial
interface. The jumpers are preset for RS-423. RS-232 is required for digital
telecommunication within the European Community.

TABLE C-16

identifies serial port

jumper settings. If the system is being connected to a public X.25 network, the serial
port mode jumper setting may need to change from RS-423 to RS-232 mode.

To change the serial port mode jumper setting:

1. Power off the system unit.

See Section 6.2, “Powering Off the System Unit” on page 6-3.

2. Remove the side access cover.

See Section 7.1, “Removing the Side Access Cover” on page 7-2.

Caution –

Use proper ESD grounding techniques when handling components. Wear

an antistatic wriststrap and use an ESD-protected mat. Store ESD-sensitive
components in antistatic bags before placing them on any surface.

3. Attach the wrist strap.

See Section 7.2, “Attaching the Wrist Strap” on page 7-3.

4. Locate the jumpers on the system board. Change the J2604 and J2605 jumper

selection.