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Sound_ControllerInfo
SoundDMA
» SWI Calls
» Sound_ControllerInfo
Sound_ControllerInfo
(SWI &4014A)
| Entry | |
|---|---|
| R0 | Pointer to space/control terminated controller ID string |
| R1 | Pointer to buffer for result, or 0 to check required length |
| R2 | Length of buffer |
| R3 | Property to read |
| Exit | |
|---|---|
| R0 | 0, or pointer to error block |
| R1 | Buffer updated with value of property |
| R2 | Length of data |
Use
This call can be used to read the properties of a specific audio controller device.
Notes
Many versions of SoundDMA do not return errors when unknown SWIs are called. Therefore, to detect if this SWI is supported, check if R0 has been set to 0 on exit (Valid reason codes start at 1), or use Sound_ReadSysInfo 1.
If the supplied buffer is not large enough, or the pointer was 0, a buffer overflow error will be generated and no data will be copied to the buffer.
See also
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