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It is possible to create sound by writing audio data one word at a time to
the audio output addresses, instead of setting up a list of audio data in
memory. This method of controlling the output is more processor-intensive
and is therefore not recommended.

To use direct audio output, do not enable the DMA for the audio channel
you wish to use; this changes the timing of the  interrupts . The normal
 interrupt  occurs after a data address has been read; in direct audio
output, the  interrupt  occurs after one data word has been output.

Unlike in the DMA-controlled automatic data output, in direct audio
output, if you do not write a new set of data to the output addresses
before two sampling intervals have elapsed, the audio output will cease
changing. The last value remains as an output of the
 digital-to-analog converter .

The  volume  and  period registers  are set as usual.