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7 - Jingles
Stringing piezo tones together to create tunes can be problematic. For instance, if you were programming it yourself, you would need to play a tone, wait for it to end, and then play another (or pause if silence requested). It can be done (for instance the call piezo_sync() makes your program wait until the current audio is finished), but it is awkward, especially when there is a much easier way - the ebm jingle call:void piezo_play_jingle(unsigned int idx, int flags);
The flags for this call are the same as for piezo_play_1tone(); however, the index value is an index to a table of preset jingles. To get this list, you use piezo_njingles(), which returns the total available (and thereby the maximum index value to use):
int piezo_njingles(size_t *nbytes);
The nbytes value is the memory required to store all the jingle names in a single array, including each string's null byte. This can be useful for efficiency, since you only need a single malloc() to set aside memory (instead of one per string), but if you plan to store names individually (or not at all), you can just ignore this value.
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