D.3 Assembly Language Samples
D.3.1 Enable the DIO Input Function
The BIOS interrupt call INT 15H controls the digital I/O. An assembly program to enable digital I/O input functions is listed below.
MOV | AX, 6F08H | Sets the digital port as input |
INT | 15H | Initiates the INT 15H BIOS call |
D.3.2 Enable the DIO Output Function
The BIOS interrupt call INT 15H controls the digital I/O. An assembly program to enable digital I/O output functions is listed below.
MOV | AX, 6F09H | Sets the digital port as output |
MOV | BL, 09H |
|
INT | 15H | Initiates the INT 15H BIOS call |
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