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[Help] IBM Model M Indicator Lights not working

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PRoman:
Hi, i have a problem with my Lexmark 1993 Model M, the keyboard works on my 2 PCs with direct ps/2 without using adapter. but the the indicator LEDs do not light. I tested with other indicator led board, and i disconnected the leds ribbon cable and i tested it conductivity with a multimeter, it works. I think it may be something related to the PS/2 port. Does anyone know how to fix it? English is not my native language, I hope it is understood

yui:
So 1st, does the board work? as does it output characters when you type on it?
 -If yes, then the problem is either likely software side (windows drivers/config, OSX/linux firmware/config) or that there is something wrong with the connections in the board, tbh my lexmark M is the terminal kind and does not have LEDs so i am out of my depths here, or it could be that the controller is damaged, but that is rather unlikely.
 -If partially (the keyboard works sometimes randomly stops, outputs long strings of the last char you pressed), then i would expect that either your usb port is not supplying enough current (if you are on a hub for example) or that your converter is not M compatible and crashes (had that with a belkin ps2 to usb, a dock with integrated converter and a random no brand in wire converter). 1st step if you are on a hub is to plug on the pc directly, 2nd is to change the converter.
 -If no, then the controller is not initializing, and that could come from a lot of things, from a dead board, dead converter, windows 8 having ps/2 capabilities disabled by default, pc/macs with incomplete USB compliance cutting power.

a lot of this comes from power, the M is a rather power hungry board, especially the old ones, so it can be rather hard to drive.

PRoman:

--- Quote from: yui on Mon, 17 May 2021, 04:26:04 ---So 1st, does the board work? as does it output characters when you type on it?
 -If yes, then the problem is either likely software side (windows drivers/config, OSX/linux firmware/config) or that there is something wrong with the connections in the board, tbh my lexmark M is the terminal kind and does not have LEDs so i am out of my depths here, or it could be that the controller is damaged, but that is rather unlikely.
 -If partially (the keyboard works sometimes randomly stops, outputs long strings of the last char you pressed), then i would expect that either your usb port is not supplying enough current (if you are on a hub for example) or that your converter is not M compatible and crashes (had that with a belkin ps2 to usb, a dock with integrated converter and a random no brand in wire converter). 1st step if you are on a hub is to plug on the pc directly, 2nd is to change the converter.
 -If no, then the controller is not initializing, and that could come from a lot of things, from a dead board, dead converter, windows 8 having ps/2 capabilities disabled by default, pc/macs with incomplete USB compliance cutting power.

a lot of this comes from power, the M is a rather power hungry board, especially the old ones, so it can be rather hard to drive.

--- End quote ---

The keyboard works perfectly (all keys work, caps lock and num lock do their job), not keys delay, not repeated chars, not stops, except for the leds, they never turn on. I'm using the keyboard directly to ps/2 port of the motherboard with the original SDL to ps/2 cable. I think is software or electrical supply issue.

PRoman:

--- Quote from: PRoman on Mon, 17 May 2021, 04:39:26 ---
--- Quote from: yui on Mon, 17 May 2021, 04:26:04 ---So 1st, does the board work? as does it output characters when you type on it?
 -If yes, then the problem is either likely software side (windows drivers/config, OSX/linux firmware/config) or that there is something wrong with the connections in the board, tbh my lexmark M is the terminal kind and does not have LEDs so i am out of my depths here, or it could be that the controller is damaged, but that is rather unlikely.
 -If partially (the keyboard works sometimes randomly stops, outputs long strings of the last char you pressed), then i would expect that either your usb port is not supplying enough current (if you are on a hub for example) or that your converter is not M compatible and crashes (had that with a belkin ps2 to usb, a dock with integrated converter and a random no brand in wire converter). 1st step if you are on a hub is to plug on the pc directly, 2nd is to change the converter.
 -If no, then the controller is not initializing, and that could come from a lot of things, from a dead board, dead converter, windows 8 having ps/2 capabilities disabled by default, pc/macs with incomplete USB compliance cutting power.

a lot of this comes from power, the M is a rather power hungry board, especially the old ones, so it can be rather hard to drive.

--- End quote ---

The keyboard works perfectly (all keys work, caps lock and num lock do their job), not keys delay, not repeated chars, not stops, except for the leds, they never turn on. I'm using the keyboard directly to ps/2 port of the motherboard with the original SDL to ps/2 cable. I think is software or electrical supply issue.

--- End quote ---
.

Now that I remember, the first week when I assembled the keyboard and used it, the LEDs were blinking a few times randomly (when caps lock was on, or num lock). after about a month, they never turned on again

yui:

--- Quote from: PRoman on Mon, 17 May 2021, 04:39:26 ---The keyboard works perfectly (all keys work, caps lock and num lock do their job), not keys delay, not repeated chars, not stops, except for the leds, they never turn on. I'm using the keyboard directly to ps/2 port of the motherboard with the original SDL to ps/2 cable. I think is software or electrical supply issue.

--- End quote ---
if it works properly it is not supply, a supply problem would prevent the board from even working at all, or would make it output very strange things. as you said that works, supply is out of the picture, and being on the ps/2 of the motherboard should also insure that.
to see if it is windows f***ing up or a problem with the board when the board initializes it blinks its LEDs, if they blink when you start the PC, the problem is software side, if it doesn't the problem is board side (this blinking is 100% board side), one other thing you could try is to enable numlock on boot, although windows 10 will disable it and you can't prevent it from doing so (thx MS), if the light is up until windows boots then that also mean the problem is software side. although further than that i will be unable to help as it would be the 1st time i see that problem.

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