IBM 6580 DisplayWriter Restoration Blog

1/7/23

We powered on the system and there was no display on the monitor. On the backside of the computer we observed that the A, B, and C LEDs were not illuminated. This means that the power supply passed diagnostics. The D through H were illuminated. Since D stays illuminated that means that either the processor, ROM, or "local I/O bus wrap" tests are not completing.

Our next step is to try to swap out the system board containing all of those components with one from another system in the warehouse which would hopefully be functional.

Pictured here are the innards of the DisplayWriter with the top cover off. The system board is on the bottom. The two boards on top are a memory board and a display card.

Pictured below, the original dusty and supposedly broken system board.

2/11/23

We went to the warehouse and got more system boards from other DisplayWriters which were in worse shape than the one we have at the Learning Lab. Hopefully one of them will work!

System board serial number 4580593-A2266XL does not seem to work - with it plugged in we no longer even get power supply good LEDs.

The other system board has some AMD chips instead of Intel - looks like a second source kind of thing. It does not work either.

It's possible that we're not putting the cards in the right slots. Will reference against manual next.

3/11/23

The cards are definitely in the right slots. We are observing different behavior with the three different system boards we have:

4466740-A5093XL - Diagnostic LEDs A-C OFF; D-H ON
4580593-A1194XL - Diagnostic LEDs A-H OFF
4580593-A2266XL - Diagnostic LEDs A-C OFF; D OFF, E-H ON

Board A2266XL gets furthest in the boot process but the diagnostic LEDs indicate that it's still failing very early (just not as early as the other boards). The fact that this board was not doing anything last month is likely user error.

We pulled the socketed ROM chips, sprayed de