All standard serial mice (Mouse Systems, Microsoft, Logitech) operate at 1200 baud.
For Microsoft and Logitech mice, the procedure for determining the mouse type is as follows:
The mouse driver first tries to determine its presence on the first COM port; if this fails, it tries the second port and, possibly, the following ones. Some drivers support only the first two ports; some need to specify the port number in the driver call parameters if the mouse is connected to the third or fourth port.
To determine the presence of a mouse, the driver sets a positive voltage of 12V on the RTS port line; the mouse must respond to this by transmitting the first byte containing the value 4Dh if the mouse is Microsoft or Logitech. This may be followed by ID bytes by which the driver can recognize a specific type of mouse.
There are three varieties of Microsoft compatible serial mice:
1. “Old” or MS - two buttons, responds only with the 4Dh byte. The mouse reports in three bytes.
2. MS+ (Logitech) - three buttons, responds with the 4Dh byte and an additional identifier. The mouse reports three bytes (the same as for MS) and an additional fourth if the middle button is pressed.
3. MS 3D – three buttons and a wheel, responds with the 4Dh byte and an additional identifier. The mouse reports four bytes (the first three are the same as for MS).
From this we can see that a driver designed to work with an MS mouse (and these are all Microsoft DOS drivers) will work with any Microsoft or Logitech mouse, but only in two-button mode. The Logitech DOS driver supports the middle button when using an MS+ (Logitech) mouse.
Determining the presence of a three-button Mouse Systems mouse is made difficult by the fact that the original standard did not provide for a mouse response to a driver request. Usually the driver assumes that the mouse is connected to the first COM port, but cannot check this. No other ports are scanned. Related to this is Mouse Systems' "detection" of the mouse, even if no mouse is connected or in the event of a faulty mouse. If the mouse is connected to a port different from the first one, then the port number should be specified in the parameters when starting the driver. Attempts have been made to develop methods for Mouse Systems to detect mice: some drivers check for the presence of a DSR - DTR connection, assuming that these lines are closed at the mouse, but this method is unreliable; mice from some manufacturers respond to the request with the 6Dh byte, and when using the appropriate driver, such a mouse can be detected by polling the ports.
I'm guessing the problem with the new Minutemanqvs mouse is due to the LEDs in the mouse not being bright enough due to not having enough current through them. All COM ports have a variation in the current they are capable of delivering along their lines. This is due to some difference in the +12 and -12V voltages in different computers, variation in the resistance of the current-limiting port lines, and differences in the current consumption of different mice. To begin with, I would suggest setting up the LED-photodiode pairs so that their lenses are strictly opposite each other and coaxial. If this does not help, you should reduce the resistance of the resistor in series with the LEDs by about 20%. On the board of this mouse, such a resistor should be located on the side of the printed conductors, apparently in an SMD design.