m1 Description
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0 Resets mouse, number of buttons returned in m2; status returned in m1
(0 indicates mouse not installed, -1 if OK)
1 Enable mouse cursor
2 Disable mouse cursor
3 Returns button status and cursor coordinates (m3 = horizontal,
m4 = vertical
4 Set mouse cursor (m3= horizontal, m4 = vertical) screen address
5 Returns button press information (set m2 = 0 for left button, 1 for right.
Number of presses are returned in m2; m3 and m4 have right cursor
position)
6 Same as (5), but gets information when button is RELEASED
7 Limits range of cursor's horizontal movement
8 Limits range of cursor's vertical movement