Husky MP2500 Manual page 204

The MP2500 BIOS provides identical functions, with the following
exceptions:
•
04H: replaced by a 'get cursor address' function, as the display
hardware does not support a lightpen.
•
0BH: not implemented.
•
10H, 11H and 12H: not implemented.
•
13H: only subfunction 00H.
While these functions are highly compatible, remember that the display
hardware is only capable of displaying two colours (black and white) and the
inverse video attribute. So, while you can use the 'colours' and attributes
that each screen mode supports, the visible result is constrained by the
hardware.
For example: If a pixel were written with the colour red, it would be
displayed as black, but its colour would be read (direct from screen memory
or via the appropriate function) as red.
MP2500 also provides a number of extended functions to provide easy
access to its special features:
60H Set graphics font
61H Move cursor to graphics co-ordinates
62H Get cursor position in graphics co-ordinates
63H Set contrast
64H Reserved
65H Get/set backlight timeout
66H Split display
70H Draw ellipse/circle
71H Draw line/box
72H Select inverse video mechanism
73H Set text font
74H Set LCD window position
75H Reserved
76H Looking keys
77H Get graphics font
78H Turn backlight on/off
79H Reset screen parameters
7AH Get contrast and backlight states
7BH Set bold attribute mask
182 H MP2500 System Developer's Guide
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