Cursor Positioning in Text Mode (19866)

The information in this article applies to:
    Microsoft Mouse driver for MS-DOS 9.0
    Microsoft Mouse driver for MS-DOS 6.x
    Microsoft Mouse driver for MS-DOS 7.x
    Microsoft Mouse driver for MS-DOS 8.x

This article was previously published under Q19866


If you use the Microsoft Mouse in a program that runs in text mode, the mouse returns cursor position values in PELs. You can convert these to character cell values by dividing them by 8.


If the mouse detects that the screen is in text mode (for example, EGA or CGA), the cursor position return values from the mouse functions are returned with MOD 8 values (the lowest three bits are 0). The outputs from the relevant mouse functions may be divided by 8, or bit-shifted right by three. Conversely, character cell positions sent to the mouse should be multiplied by 8 (or bit-shifted left by 3).

Modification Type: Major Last Reviewed: 9/24/2003
Keywords: KB19866