Sound Voice Generator Instantiate (changes)
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Programmer's SoundChannels Reference Manuals
» Part 15 – SWI Calls?SWI Calls
» Sound Sound_InstallVoice
» Sound_InstallVoice Sound Voice Generator
» Sound Voice Generator
Voice Generator Instantiate
The Instantiate entry is called to inform the Voice Generator of a request to attach a channel to it.
| Entry | |
|---|---|
| R0 | Channel number |
| R5 | Pointer to Voice Generator |
| Exit | |
|---|---|
| R0 | Preserved if the Instantiation was successful, else it is altered. |
| R1-R4 | Preserved |
| R5 | May be corrupted |
| R6-R12 | Preserved |
Notes
The Voice Generator is entered in SVC mode.
To return to the Channel Handler use LDR PC,[R13],#4
A Voice Generator should ideally be able to support eight channels. The request can either be accepted (R0 preserved on exit), or rejected (R0 altered on exit).
The usual reason for rejection is that an algorithm is slow and is already filling as many channels as it can within each buffer period: for example very complex algorithms, or ones that read long samples off disc.
See also
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