Step 5 Set Jumpers, Continued

J1 Termination Enable J1 is a three-pin header that specifies hardware or software control of SCSI termination.

Type of SCSI Termination

Software control of SCSI termination via drive detection.

Permanently disable all onboard SCSI termination.

Permanently enable all onboard SCSI termination.

J1 Setting

Short Pins 1-2

Short Pins 2-3

OPEN

J3 I2C Interface Connector J3 is a four-pin header that allows the i960JX core processor to serve as a master and slave device that resided on the I2C bus when used with the I2C Bus Interface Unit. Attach a four-wire cable from J3 to the I2C Bus Interface Unit.

J4 Serial Port J4 is a 9-pin berg that attaches to a serial cable. The pinout:

Pin

Signal Description

Pin

Signal Description

1

Carrier Detect

2

Data Set Ready

3

Receive Data

4

Request to Send

5

Transmit Data

6

Clear to Send

7

Data Terminal Ready

8

Ring Indicator

9

Ground

 

 

J5 Hard Disk LED J5 is a four-pin connector that attaches to a cable that connects to the hard disk LED mounted on the computer enclosure. The LED indicates data transfers.

PinDescription

1High

2SCSI Activity Signal

3SCSI Activity Signal

4High

Cont’d

Chapter 6 Hardware Installation

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