Sun Microsystems 220R service manual How to Set the Serial Port Jumpers

3.15How to Set the Serial Port Jumpers

The serial port jumpers on the main logic board (J2604 and J2605) permit the configuration of the system's two serial ports for either EIA-432 or EIA-232D signal levels. EIA-432 levels are the default standard for North American users. EIA-232D levels are required for digital telecommunication in nations of the European Economic Community.

For further information, see your Sun Enterprise 220R Server Owner's Guide.

3.15.1Before You Begin

Complete these tasks:

Section 2.1 “How to Power Off the System” on page 54

Section 2.4 “How to Position the System for Service” on page 60

4Section 2.6 “How to Remove the System Cover” on page 65 Section 2.8 “How to Avoid Electrostatic Discharge” on page 69

3.15.2What to Do

1.Locate the jumpers on the main logic board.

A main logic board jumper is identified by its jumper address, labeled on the board with the letter “J” followed by four numbers (JXXXX). Jumper pins are located immediately adjacent to the jumper address. On the board, pin 1 is marked with an asterisk.

122 Sun Enterprise 220R Server Service Manual ♦ January 2000, Revision A