AN3143

Conclusion

Doc ID 17011 Rev 1

11/13

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Conclusion

This application note offers an easy-to-use application solution for the STM8S with good

quality audio/speech output. To adequately reduce memory space which allows an audio

bitstream to be stored, an IMA ADPCM codec is implemented. Short audio clips can be

stored directly in the internal program memory. To store long length audio clips, an external

memory is needed. The SD card was used as an example in this application note.

The STM8S audio output solution was developed with the aim to limit external components.

This solution benefits from the STM8S timer with dual PWM output to reach 16-bit

resolution.

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References

IMA Digital Audio Focus and Technical Working Group, Recommended Practices for

Enhancing Digital Audio Compatibility in Multimedia Systems, revision 3.00, October 21,

1992. No longer available on http://www.ima.org.

Maël Hörz, HxD, revision 1.7.7.0 - hexa editor, http://mh-nexus.de.