"Crazy Mouse Syndrome" on Win7_64

Development Tools IDE 1.x
1

Maybe this info is usefull to somebody.
A few weeks ago, maybe after some update, my Arduinos (CH340 serial) started to behave like mice.
As soon as I plugged them into a USB port, the cursor started to jump, and the normal (wireless USB) mouse became unresponsive. Unplugging the Arduino instantly cured it.
Every trick I could find on the net failed (COM below9, new drivers, etc.).
Untill I came across this page.
http://www.taltech.com/support/entry/windows_2000_nt_serial_mice_and_missing_com_port

In the registry;
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\sermouse
Change start entry from value 3 to value 4
I had two of those "control sets", so I changed both.
After a restart the problem solved.
Leo..

2

Two weeks without problems, and the Windows bug is back.
Maybe after some update, dunno.

I went into the registry, and see about 50 "sermouse" events.
Desperate, so I clipped most of them.

All good again.

Reminds me of the movie "Mouse Hunt".
Maybe someone has a permanent solution.
Leo..

3

That is really spooky.

I wonder if the sketch is sending something down the wire right after startup that makes windows think it's a mouse, after which it "remembers" that that serial port has a mouse connected.

4

That taltech.com article you gave the link to is interesting. It makes me think perhaps you left the Arduino connected to the PC while you reboot the PC.

You could possibly upgrade your bootloader on the Arduinos to a different one, such as the latest Optiboot. The latest Optiboot does not attempt to talk on the serial port during power up of the Arduino.

5

My PC is always on suspend (hybernate).
I reboot only if I have to, e.g. after a windows update or powercut.
Leo..