VAXstation 3100 Troubleshooting Guide

Fault-finding on the VAXstation 3100 uses the firmware's power-up tests, the eight diagnostic LEDs on the back of the system box, and the procedures in DEC's VAXstation 3100 Maintenance Guide (EK-285AA-MG-001), which covers the Models 30 and 40.[1][2] The power supply is covered on VAXstation 3100 Power Supply Guide.

Rear panel of the Model 30, with the eight diagnostic LEDs to the right of the printer port (DEC, EK-285AA-MG-001, Figure 4-1)

DEC asks for a static wrist strap and mat when handling the FRUs, and warns against unplugging the keyboard, mouse or tablet with the power on.[3][4]

Normal power-up

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When the system is switched on, the green power light comes on and the LEDs on the back count down in hexadecimal. Within two minutes the countdown appears on the screen, the available boot devices are listed, and if no boot device is entered within two more minutes the system boots from the Ethernet (ESA0).[5] DEC allows two to five minutes for power-up testing to finish.[6]

The screen countdown starts with the CPU name and ROM version (KA42-A V1.0 on a Model 30) and runs from test F to test 1. The mark after each test number means:[7]

  • a full stop: the device passed, or has a soft error;
  • ?: a hard error;
  • _: no option device installed, so no test;
  • *: an option is installed but its ROM code has not run, and the option must be replaced.

A summary follows the countdown: ?? marks a hard error, which must be cleared by replacing the failing FRU before booting, and ? a soft error or status report. Each line gives the test number, the device ID and an eight-digit code. Enter TEST 50 to see the configuration table, which lists every device and its status.[7][8]

Power-up tests (DEC Table 1-4)
Test Mnemonic Device
F MONO Base monochrome video
E CLK Time-of-year clock
D NVR Nonvolatile RAM
C DZ Serial line controller
B MEM Memory
A MM Memory management
9 FP Floating point
8 IT Interval timer
7 STRG-1 or SCSI-A RX23 controller (Model 30 ST506/SCSI) or SCSI-A bus
6 SCSI-B SCSI-B bus
5 SYS Interrupt controller and Ethernet ID ROM
4 8PLN 8-plane graphics module
1 NI Ethernet

[9][10]

Common status codes

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Power-up status messages (DEC, EK-285AA-MG-001, pp. 9 to 10)
Summary line Meaning Action
? E 0040 0000.0005 Clock not set Set the time when the operating system is installed; the code clears at the next clock test
? D 0050 0000.0005 NVR battery charge low Leave the system powered; DEC quotes about 17 hours for a full recharge
?? 1 00C0 0000.7004 ThinWire Ethernet connector not terminated Fit a terminator or a properly terminated cable
?? 1 00C0 0011.700E Standard Ethernet connector or cable not terminated Terminate the connector or correct the cable

[11]

For the NVR, a code of 0000.0001 means no errors. Any code other than 0000.0001 or the low-battery code means the system module must be replaced, since the NVR is on it. If the low-battery code does not clear within an hour of continuous running, check the battery cable, then replace the battery and let it charge for 24 hours.[12]

Diagnostic LEDs

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The eight LEDs on the back of the system box form two groups of four. The first four show the state of the system and the second four a substate (1 = lit):[2]

Diagnostic LED states (DEC Table G-1)
State Substate Meaning
1111 1111 Power applied, no instruction executed
1111 0000 ROM code started and running
1110 0000 Console memory sizing
1101 0000 Console data structures initialised; NVR test started
1100 0000 NVR test complete; DZ test started
1011 0000 or 0001 DZ test complete; optional video found (0000) or base monochrome video test entered (0001)
1010 0000 Video tested; console initialisation entered
1001 test code Power-up tests running; the substate shows the test
1000 test code Self-test complete; the substate shows the failing subsystem

[2]

The substate codes for tests are 1111 MONO, 1110 CLK, 1101 NVR, 1100 DZ, 1011 MEM, 1010 MM, 1001 FP, 1000 IT, 0111 STRG-1 or SCSI-A, 0110 SCSI-A or SCSI-B, 0101 SYS, 0100 8PLN and 0001 NI.[2] If the state LEDs stop between 1111 and 1010, the substate does not identify the fault, and DEC's isolation procedure below applies.[6]

Dead system or no video

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Check the basics first: the video cable at both ends, that the monitor is on with its LED lit, and the brightness. Then check switch S3 on the back of the system box: down when the monitor is the console, up when a terminal on the printer port is the console (at 9600 baud).[13]

DEC's isolation procedure disconnects one FRU at a time until the system powers up normally; the last FRU removed is the faulty one:[13][6]

  1. Power down, remove the cover, and disconnect the cable from the system module to the MSC module and the power cables to the drives. Power up. If the system now works, reconnect the MSC module, then the drives one at a time, to find the culprit.
  2. Power down, remove the drive mounting panel and take the graphics module off the system module. Without it there is no video, so set S3 up and use a terminal on the printer port, or watch the LEDs. Power up.
  3. Power down and remove the memory module. Power up.
  4. Replace the system module. If the system still does not power up, replace the power supply.

When fitting a replacement system module, move the Ethernet ID ROM across from the old one, with pin 1 (the notch) the same way round.[14]

Monitor faults

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Monitor troubleshooting (DEC Table 2-17)
Symptom Corrective action, in order
No LED, no raster Check the power cord, the 120/240 V setting and the fuse; then the monitor's own service guide
Compressed raster, no video Check the monitor cable and that it is the right type (BC18P-type without a graphics module; BC19S or BC23J-03 with one); adjust contrast and brightness; run TEST F (no graphics module) or TEST 4 (graphics module) and replace the failing module
Raster but no video Adjust contrast and brightness; run TEST F or TEST 4 as above
No LED but good video Replace the monitor's LED assembly

[15] DEC's guides for the monitors are the VR150 and VR160 pocket service guides, the VR260 maintenance advisory and the VR290 service guide.[3]

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References

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  1. ↑ Digital Equipment Corporation, VAXstation 3100 Maintenance Guide, EK-285AA-MG-001, February 1989, p. 3, section 1.2 (File:VAXstation 3100 Maintenance Guide (EK-285AA-MG-001).pdf).
  2. ↑ 2.0 2.1 2.2 2.3 DEC, EK-285AA-MG-001, pp. 242 to 243, Appendix G, Table G-1, "Diagnostic LEDs Definitions".
  3. ↑ 3.0 3.1 DEC, EK-285AA-MG-001, pp. 90 to 91, section 4.2, caution and Table 4-2.
  4. ↑ DEC, EK-285AA-MG-001, p. 106, section 4.2.12.
  5. ↑ DEC, EK-285AA-MG-001, p. 20, section 2.2 and Figure 2-1.
  6. ↑ 6.0 6.1 6.2 DEC, EK-285AA-MG-001, pp. 244 to 245, section G.1.
  7. ↑ 7.0 7.1 DEC, EK-285AA-MG-001, pp. 4 to 5, Figures 1-1 and 1-2 and Table 1-2. Power-up display and symbols.
  8. ↑ DEC, EK-285AA-MG-001, p. 5. Hard and soft errors; TEST 50.
  9. ↑ DEC, EK-285AA-MG-001, p. 6, Table 1-4.
  10. ↑ DEC, EK-285AA-MG-001, p. 53, sections 2.19 and 2.20. TEST 5 (SYS) and TEST 4 (8PLN).
  11. ↑ DEC, EK-285AA-MG-001, pp. 9 to 10. Common power-up status messages.
  12. ↑ DEC, EK-285AA-MG-001, p. 24, sections 2.5 and 2.5.1. NVR.
  13. ↑ 13.0 13.1 DEC, EK-285AA-MG-001, pp. 21 to 22, section 2.2.1. No video display.
  14. ↑ DEC, EK-285AA-MG-001, p. 104, section 4.2.9. Ethernet ID ROM.
  15. ↑ DEC, EK-285AA-MG-001, p. 60, section 2.23 and Table 2-17.