User:Johnburger/Demo/BIOS/VGA
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< User:Johnburger | Demo
Most of the screen handling is done by directly accessing the memory, so Dev/VGA defines a large number of symbols for use.
The BIOS implements the tricky (and usually proprietary) part of changing the current display mode. Here are the definitions for that.
Demo/BIOS/VGA.inc
; ; BIOS/VGA.inc ; ; These are the definitions for the BIOS video controller BIOS.VGA.Int EQU 10h BIOS.VGA.SetMode.Fn EQU 00h BIOS.VGA.SetMode.80x25 EQU 03h BIOS.VGA.ExtMode.Fn EQU 11h BIOS.VGA.ExtMode.80x50 EQU 12h BIOS.VGA.Cursor.Fn EQU 01h BIOS.VGA.Cursor.None EQU 0010_0000_0000_0000b BIOS.VGA.Cursor.Under EQU 06_07h BIOS.VGA.Cursor.Block EQU 00_07h