Western Digital WDM2, WDM20 Motherboards, and PS/2 Mouse Port (63921)


The information in this article applies to:

  • Microsoft Windows 3.0
  • Microsoft Windows 3.0a
This article was previously published under Q63921

SUMMARY

The Microsoft Mouse does not function properly on a Western Digital WDM2 or WDM20 motherboard if it is connected to the PS/2 mouse port. The keyboard ROM on this motherboard causes erratic mouse movement when Windows is in standard or enhanced mode.

MORE INFORMATION

There are four possible corrections to the problem, as follows:
  • Connect the mouse to one of the serial ports.
  • Use a bus mouse such as the Microsoft or Logitech bus mouse.
  • Send the motherboard to a Western Digital Service center to have the keyboard ROM chip replaced.
  • Modify the HIMEM.SYS line in the CONFIG.SYS file to read HIMEM.SYS /M:2.
The PS/2 mouse port on a non-PS/2 computer is a special adapter port on the machine. You use a serial mouse with a special adapter on one end to connect to this adapter port. The PS/2 mouse port uses a hardware specific interrupt (usually IRQ12) to communicate with the mouse instead of the normal serial ports that are on IRQ3 and IRQ4.
Modification Type:MinorLast Reviewed:7/7/2005
Keywords:KB63921
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