There have been some reports that certain model of PS/2 mouse from MouseSystems works only if it is put into the ``high resolution'' mode. Otherwise, the mouse cursor may jump to the upper-left corner of the screen every so often.
Unfortunately there is no workaround for versions 2.0.X and 2.1.X. In versions 2.2 through 2.2.5, apply the following patch to /sys/i386/isa/psm.c and rebuild the kernel. See the section on building a kernel if you have no experience with building kernels.
@@ -766,6 +766,8 @@ if (verbose >= 2) log(LOG_DEBUG, "psm%d: SET_DEFAULTS return code:%04x\n", unit, i); + set_mouse_resolution(sc->kbdc, PSMD_RES_HIGH); + #if 0 set_mouse_scaling(sc->kbdc); /* 1:1 scaling */ set_mouse_mode(sc->kbdc); /* stream mode */
In versions 2.2.6 or later, specify the flags 0x04 to the PS/2 mouse driver to put the mouse into the high resolution mode. Enter UserConfig by giving the -c option at the boot prompt:
Then, in the UserConfig command line, type:
UserConfig> flags psm0 0x04 UserConfig> quit
See the previous section for another possible cause of mouse problems.