Terminal Model M Problems

pyr099

03 Feb 2023, 07:51

Hello all, been having issues getting a terminal Model M #1395665 to work. I bought it off ebay with a Pro Micro already installed, but no matter what I do nothing happens when I type. I've tried flashing Soarer's converter, TMK, and QMK to it to no avail. I also tested the connections from the Pro Micro to the keyboard's board and everything seems to be correct. hid listen with Soarer's installed gives me this:

Code: Select all

Waiting for new device:...
Listening:
rAA r7F r7F r00 r00 wEE rEE wF2 rFA r7F r7F

remaining: FFFC
wF8 rFA

Keyboard ID: 7F7F
Code Set: 3
Mode: AT/PS2

wED rFA w02 rFA
r00
r00
r00
r00
r00
r00
Any help would be greatly appreciated.
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pandrew

03 Feb 2023, 15:57

Looks like the keyboard is detected, it identifies scan code set 3 correctly.
Do any new "rNN" messages show up while trying to type? (Maybe the keymap is set up to not send anything, but you should still see it in hid_listen).
Can you get it to type anything by shorting a row to a column with a wire? for example if you short these two pins, I think they map to the Q key (maybe the keyboard has been massively water damaged, and the membranes are dead, that's what you test with this.):
example_short.png
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Next, this is not causing your current problem, but J1 pads on the pro micro should be shorted. After you have solved the current issue, make sure to short it.

pyr099

04 Feb 2023, 02:18

Typing does nothing, I shorted those pins and a few other combinations and still nothing on hid_listen, still getting the repeating "r00".

AngryCockroach

05 Feb 2023, 12:15

Hi, I see the J1 jumper on the pro micro is open.
I soldered it closed on all my M122 because I read the micro provides more power to the keyboard then.

pyr099

06 Feb 2023, 01:58

Soldered it closed today, still no change unfortunately. I have noticed that a bunch of commands get sent when I jiggle the ribbon cables.

pyr099

06 Feb 2023, 09:10

Ok so I ended up desoldering the Pro Micro, completely disassembling the keyboard, put everything back together, resoldered the Pro Micro, and now everything works flawlessly. No clue what it could have been, my money is on a loose connection from the seller that I missed somehow. Am currently typing this with it. :D Thanks to everyone for all the help.

User avatar
Muirium
µ

06 Feb 2023, 12:49

Sometimes the maximalist approach is the right approach. ;)

Congratulations on your successful fix.

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