First post, by lackofpatience
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- Newbie
Hey everyone,
I'm hoping someone might have some pointers for 286 keyboard controllers.
I've got a DTK PTM-1010 v2, 286 Motherboard I saved from the recycling center.
https://theretroweb.com/motherboards/s/dtk-pt … 10v2-edit.-1.01
Like most of these motherboards, the battery had leaked and cut some traces. Overall the damage wasn't too bad. I only needed to bridge 4 traces with wire, from my testing.
I've got the machine to a point where it will POST past a memory count and won't show the previous keyboard fault code 0742. This code would show pre memory count before I did some repairs, not completing post. Now I get passed this error code and completes a memory count and continues to post.
So it seems now the keyboard controller is being detected at least.
Now I'm getting an error for "User to check keyboard" Aka a keyboard detection issue.
Where I'm kind of stuck is with two questions.
1. Do most 286 machines require a XT compatible keyboard?
2. Am I missing a signal to/from the keyboard controller or keyboard port? See continuity tests bellow
I don't know about question 1.
But if someone could eyeball the following testing to see if I'm missing something obvious. Hopefully I get some pointers.
For question 2, I have done the following continuity tests from the keyboard controller chip to the Keyboard port. Also have check that +5v and Grounds are connected.
Keyboard LED's do now flash when I power the motherboard up. No caps lock or num lock toggles work and the keyboard is still not detected. Before the trace repair, no LED's would light up at power up.
I tested the following by going over each socket pin and checking which pin has the lowest resistance in continuity mode. Please forgive my lack of skills, I'm not familiar with testing such IC's.
At this point I'm not sure if I'm missing a connection to the controller or if it's simply a AT vs XT keyboard compatibility issue?
Something odd was for ground, the VSS and Pin 7 EA pin are connected to some sort of ground. Perhaps that is correct, I'm not sure.
Anything that I'm missing from the above or things worth checking?
Cheers!
