weedeewee wrote on 2024-02-02, 19:02:

For a normal cable resistance value, those values are a bit too high. your cable is suspect. From my own experience, where the […]
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For a normal cable resistance value, those values are a bit too high. your cable is suspect.
From my own experience, where the cable enters the mouse tends to be prone to cable breakage, that or the connector side. The two places were the cables tends to be bent and stretched in a 90° angle.

I recently recovered a broken microsoft mouse (made by mitsumi) and compared the resistance values for that one with yours and all resistance values are less than 1 ohm.
The pins on the serial connector are the same.

edit: try measuring the resistance while playing/bending the cable at those points mentioned.

I think we have a winner. The GND cable varies up to 500 Ohm while bending.

Minutemanqvs wrote on 2024-02-02, 21:53:

weedeewee wrote on 2024-02-02, 19:02:

For a normal cable resistance value, those values are a bit too high. your cable is suspect. From my own experience, where the […]
Show full quote

For a normal cable resistance value, those values are a bit too high. your cable is suspect.
From my own experience, where the cable enters the mouse tends to be prone to cable breakage, that or the connector side. The two places were the cables tends to be bent and stretched in a 90° angle.

I recently recovered a broken microsoft mouse (made by mitsumi) and compared the resistance values for that one with yours and all resistance values are less than 1 ohm.
The pins on the serial connector are the same.

edit: try measuring the resistance while playing/bending the cable at those points mentioned.

I think we have a winner. The GND cable varies up to 500 Ohm while bending.

Yep, that'll lead to frustrations.

Minutemanqvs wrote on 2024-02-02, 21:53:

weedeewee wrote on 2024-02-02, 19:02:

For a normal cable resistance value, those values are a bit too high. your cable is suspect. From my own experience, where the […]
Show full quote

For a normal cable resistance value, those values are a bit too high. your cable is suspect.
From my own experience, where the cable enters the mouse tends to be prone to cable breakage, that or the connector side. The two places were the cables tends to be bent and stretched in a 90° angle.

I recently recovered a broken microsoft mouse (made by mitsumi) and compared the resistance values for that one with yours and all resistance values are less than 1 ohm.
The pins on the serial connector are the same.

edit: try measuring the resistance while playing/bending the cable at those points mentioned.

I think we have a winner. The GND cable varies up to 500 Ohm while bending.

That much resistance on the ground wire means the ground the IC in the mouse sees is no longer 0V referenced. That will definitely mess up your day.

Minutemanqvs wrote on 2024-02-02, 21:53:

I think we have a winner. The GND cable varies up to 500 Ohm while bending.

STRRRRRRIKE!
So you know where to cut and shorten the cable.

To give a full feedback:

On my second mouse which worked better I actually have a similar cable problem, it's just less pronounced. So I was just "incredibly" (considering it's old second-hand hardware) unlucky to have 2 mice with the same issue.

So I bought the third 3€ mouse , also a Logitech. This one works like a charm on all 3 systems. I opened it, took the cable and connected it to the 2 other faulty mice and...they all work perfectly fine. So the 2 cables are the culprit (on the COM port end for one, on the mouse side for the other).