Ccb Diagnostic Check - Printronix

P9212 Maintenance Manual

CCB Diagnostic Check

This procedure checks the operation of the microprocessors and IC chips on
the Common Controller (CCB) and Mechanism Driver boards. Do the steps
in the order presented.
1. Set the power switch to off.
2. Remove the front panel and card cage cover. Reseat the CCB and Mech
Driver boards.
3. Set the power switch to on. Wait at least 15 seconds; while you are
waiting watch the 68010 LED at location A2 on the CCB (some boards
may be silk–screened as "68000") and watch the display on the control
panel. (NOTE: IC locations are shown in Appendix C.)
a. When the CCB is operating correctly, the control panel displays
b. If the 68010 LED never turns on, it means the 68010 did not
c. If the 68010 LED stays on for 30 seconds but never blinks, it
4–30
"Diagnostic Tests in Progress," and the 68010 LED turns on for 1
to15 seconds, then turns off. The 68010 LED turns off after the
68010 successfully tests itself, RAM, 68010 ROM, and
communication with the 64180 CPU. The more RAM or ROM
installed in the printer, the longer the LED is on, but it always turns
on then off when the CCB is functioning correctly. If the printer
turns on normally, the CCB is okay. Turn power off and return the
printer to normal operation.
If the 68010 LED turns on and off as described above, but the printer
does work properly, or fails later, go to step 4.
("Dynamic RAM Fault" on the display can mean the 64180 has
waited 15–20 seconds without getting its handshake from the 68010.
The following substeps use the 68010 LED to fault isolate this
message.)
execute the first software instruction in its ROM. Go to step 5.
means RAM and ROM for the 68010 are okay, but the 64180 is not
executing instructions. Go to step 6.
Troubleshooting