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.
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