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Using the Sound Card->
Based on the information from a page by Wouter Bergmann Tiest I made this summary
on how to use low level instructions to operate a soundcard:
Code:
Base = ?
Comm = Base + 12
Input = Base + 10
Reset = Base + 6
Comm 16 Command to output byte
Comm 32 Command to input byte
Comm 209 Turn speaker on
Comm 211 Turn speaker off
Comm Byte Output value
Reset 0 Reset speakers
Reset 1 Command to reset speakers
Waits until soundcard is ready for the next instruction.
WaitUntilReady:
MOV DX,Comm
IN AX,DX
AND AX,128
CMP AX,0
JE WaitUntilReady
There is one piece of information missing though and
that is how to set the volume for the speakers.
All I know is that it involved sending a byte to
a port formatted like this:
The first four bits specified the volume for the left
speaker and the second four bits specified the
volume for the right speaker. (Or was that the other way
around?)
Any way:
What I like to know if any one knows to which port
you need to send the byte specifying the volume
and if you need to send a command that says "set the volume"
first?