Service_Sound 9
Programmer's Reference Manuals
» Part 16 – Service Calls
» Service_Sound
» Handler Types
» Service_Sound 9
Service_Sound 9
| Entry | |
|---|---|
| R0 | 9 (reason code) |
| R1 | &54 (Service call number) |
| Exit | |
|---|---|
| – | All registers preserved |
Notes
This service call is made by SoundDMA when sound output is starting, i.e. when sound is turned on by a call to SWI Sound_Enable. It will be made before the first buffer fill request occurs. It is provided as a hint for any software that buffers audio in realtime, e.g. video playback software that needs to keep audio in sync with video, internet radio services, etc.
This call may be called with interrupts disabled; software should be careful not to re-enable interrupts or perform slow operations which will hinder the interrupt latency of the system.
Use SWI Sound_ReadSysInfo 1 to determine whether the version of SoundDMA present on the system generates this service call.
This service call should not be claimed.
See also
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