mov dl, OutputChar ;character to output
mov ah, 04h ;Auxiliary Output
int 21h
Auxiliary Output (Function 04h) sends a character to the auxiliary output device.
This function has been superseded by Write File or Device (Function 40h).
OutputChar
Specifies the ASCII value of the character to be displayed.
This function has no return value.
If the output device is busy, this function waits until the device is ready.
Function 03h Auxiliary Input
Function 40h Write File or Device