Specifications

SQ: 1-16
RS3: Service Quick Reference Guide
Troubleshooting
Console Power-Up Tests (continued)
Item DefinitionTest
Video
Generator
Color Test Tests for shorts between the RGB lines. An
error c ould be a board fault or a cable fault.
DAC Test Test of the Digital to analog Converter which
measures voltages on the RGB output lines to
the monitor. An error here can indicate that a
video driver has failed s o the card must be
replaced. It could also indicate that the monitor
is not properly terminated, the video cables are
damaged, that the shields are shorted to
ground, or the type of c able is wrong.
PIT Test Test of the Parallel Interface Timer which is
used to control interrupts. If a fault is indicated
the Video Generator card should be replaced.
RAM Test Addressing and data test is run on the RAM in
the Video Generator. If a fault i s indicated here
the card should be replaced.
Synch Test Tests synch signal rates. If a fault is indicated
the Video Generator card should be replaced.
Tape Drive Test to check for the presence of the tape drive
SCSI controller board and checks for tape
ready signal. If no tape is installed the tape
indication will be backlit blue. If a tape is
present, it will rewind the tape.
NOTE: If the cable between SCSI controller
card located on the tape unit and the tape unit
is disconnected, this test will not indicate a fault
without a tape installed. This can be verified by
installing a tape in the unit and the tape test
should not be in the blue color.
Winchester Tests to check for disk ready signal, and
verifies the integrity of several sections of the
disk to make sure it works properly.
NOTE: If the cable between the SCSI
controller c ard l ocated on the disk unit and the
disk unit is not connected, both the disk and
tape unit will indicate fault by being backlit in
red.