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Re: Strange mouse behavior

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Hey Bob.  

I happened to write a UNIX PC mouse tester program today, if you have an Arduino handy, you could try testing it out. The data is sent from the mouse in 3-byte packets at 1200 baud. I believe there's logic in the keyboard that then marshals the keyboard inputs with the mouse inputs and sends this to the 6850 chip on the motherboard. The mouse packets are only sent when an update occurs, e.g. button press or release, or an x or y mouse movement. Because the cursor flickers, it sounds like the packets are coming into the motherboard, but the x and y data isn't updated. Maybe something wrong with the x/y encoders in the mouse. You could try my test program if you wanted to confirm that the X and Y data is in fact being sent as zero -- and then you would know the problem isn't being introduced as it passes through the keyboard. If the X/Y data is correct, then it could be something introduced in the keyboard, but that seems unlikely if the mouse button presses are making it through. Looking at a pic of the mouse internals, I see a resistor, a couple capacitors, some optical encoders, 4Mhz crystal, a transistor, and the Motorola mystery chip SC87347P. Not sure where the culprit would be. Here's the link to the mouse tester: https://github.com/agentbooth/3b1mouse/tree/main/3b1MouseTester

 Jesse

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Strange mouse behavior Bob Alexander <google@loadaccumulator.com> - 2021-06-16 07:58 -0700
  Re: Strange mouse behavior J Booth <166sunny@gmail.com> - 2021-06-17 20:24 -0700
    Re: Strange mouse behavior Bob Alexander <google@loadaccumulator.com> - 2021-06-18 07:29 -0700
      Re: Strange mouse behavior Bob Alexander <google@loadaccumulator.com> - 2021-06-18 08:01 -0700
        Re: Strange mouse behavior J Booth <166sunny@gmail.com> - 2021-06-18 20:17 -0700
        Re: Strange mouse behavior Peter Schmidt <peter@transcend.aero> - 2021-06-22 04:37 -0700
          Re: Strange mouse behavior Bob Alexander <google@loadaccumulator.com> - 2021-08-05 10:41 -0700
            Re: Strange mouse behavior Peter Schmidt <peter@transcend.aero> - 2021-08-06 09:23 -0700
            Re: Strange mouse behavior djg@pdp8online.com (David Gesswein) - 2021-08-10 16:45 +0000
              Re: Strange mouse behavior Bob Alexander <google@loadaccumulator.com> - 2021-08-10 10:02 -0700
    Re: Strange mouse behavior Bob Alexander <google@loadaccumulator.com> - 2021-06-19 07:52 -0700
      Re: Strange mouse behavior J Booth <166sunny@gmail.com> - 2021-06-20 21:15 -0700

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