Functional Unit Troubleshooting; Scsi Test Connector - HP 340 Series Service Manual

Functional Unit Troubleshooting
A functional unit is one that passes the minimulll configuration test. It doesn't have to function
properly, but at least start the self-test and light the test LEDs.
SCSI Test Connector
Note
To allow complete self-tests of the SPU when the SCSI board is
installed, an SCSI test connector must be connected to the SCSI
interface port or cable.
An SCSI test connector (1252-2297) provides loop-back test information to the SCSI interface.
The connector can be used in either single-ended or differential configurations. It connects to
the SCSI port like the cable.
'Two loop- back configurations are present on the SCSI test connector:
• Single-Ended .
• Differential.
Each is explained in Table 5-2.
Table 5-2. SCSI Test Connector Configurations
SCSI Type
Single-Ended Connects to SCSI interface port on rear of SPU, or
Connects to peripheral end of SCSI interface cable, or
Replaces SCSI Terminator on SCSI peripheral.
Differential Not implemented for Model 340 Workstations.
Trou bleshooting
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