Front Panel Madness

[AltairClone]

Ok, if A1 is not stuck on, that changes everything about what we need to look for. The video is a bit grainy for me, but it appears that HLTA is on?

Mike

[AltairClone]

Hopefully unlocked now...

[Ttpilot]

Here is a better version of the video http://hawken.sdsmt.edu/8800panel1080p.mov

Yes, the HLTA light is on since I swapped chips around. In the earlier picture I sent it was off. I put all the original chips back, but HLTA is still on

Here are pics of the two boards. Maybe you can see somewhere where I screwed up

Front panel interface

[AltairClone]

Between the D4 issue, HLTA issue, and examine problems, these could all be caused by bad 8T97s. Do you have some 74LS367s you can use instead?

Mike

[Ttpilot]

Between the D4 issue, HLTA issue, and examine problems, these could all be caused by bad 8T97s. Do you have some 74LS367s you can use instead?

Mike

I'll hunt around

[Ttpilot]

I had an LS367 lying around. I swapped it out for IC-B and the A1 light went away. I found a few others on old boards and swapped them in, too. Back to the A1 light being on. I put the 8T97s back in, except for the LS367 at IC-B, and the A1 light is still on. Now I'm not sure if it was IC-B I swapped out to start with. I'm stumped

I've ordered a new set of LS367s to replace the 8T97s. Should have them in a couple of days

[AltairClone]

What happened with the D4 problem and the HLTA light problem while you were swapping parts?

Mike

[Ttpilot]

No change with the LS367 in it

[AltairClone]

No change with the LS367 in it

Sorry, but I’m confused because I have no idea exactly what you’re changing. There are numerous 8T97s on the CPU board. IC-B might affect the A1 problem. IC-E might affect the D4 problem. IC-G might affect the HLTA problem. You say no change with the LS367 in “it.” What position is “it?” And I thought you found and tried multiple LS367s, not just one (“it”). Please let me know specific tests and specific results.

Mike

[Ttpilot]

I've now got a 367 in IC-B, IC-E, and IC-G. For some reason I had them in different spots until now. I'll do a quick video of the results