Sound Voice Generator (changes)
Showing changes from revision #6 to #7:
Added | Removed | Changed
Programmer's SoundChannels Reference Manuals
» Part 15 – SWI Calls
» Sound Sound_InstallVoice
» Sound_InstallVoice
Voice Generator
| Offset | Contents | |
|---|---|---|
| +0 | B Fill | |
| +4 | B Update | |
| +8 | B GateOn | |
| +12 | B GateOff | |
| +16 | B Instantiate | |
| +20 | B Free | |
| +24 | LDR PC, [R13], #4 (was Install) | |
| +28 | Offset from start of voice generator block to voice name |
Notes
The Fill, Update, GateOn and GateOff entries provide services to fill the DMA buffer at different stages of a note.
The Instantiate and Free entries provide facilities to attach or detach the Voice Generator to or from a channel.
The Install entry was originally to be called when a Voice Generator was initialised. Since Voice Generators are now implemented as Relocatable Modules, which offer exactly this service in the form of the Initialisation entry point, this field is not supported and simply returns to the caller (LDR PC,[R13],#4 above).
The voice name is used by the Channel Handler voice table. It should be both concise and descriptive. The offset must be positive relative – that is, the voice name must be after the header.
See also
Social
and
ROOL Store
Buy RISC OS Open merchandise here, including SD cards for Raspberry Pi and more.