DMA completed callback (changes)
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DMAManager
» DMA callback routines
» DMA completed callback
DMA completed callback
| Entry | |
|---|---|
| R0 | Pointer to RISC OS error block (V flag will also be set) |
| 0 (V flag clear) | |
| R11 | Value of R2 from DMA_QueueTransfer call |
| R12 | Value of R5 from DMA_RegisterChannel call |
| Exit | |
|---|---|
| - | All registers preserved |
| Processor in IRQ or SVC mode |
| IRQ & FIQ status undefined |
Use
This callback will be called once a transfer has completed, whether it was a success (R0=0, V clear) or a failure/early termination (R0=error, V set). Prior to this callback being made, the DMA disable callback will have been called and the scatter list will have been brought fully up to date.
Note that as soon as this callback is called the DMA tag associated with this transfer is no longer valid.
Notes
This documentation only covers the RISC OS 5 version of the DMAManager SWIs. For other OS versions, consult the appropriate PRM volume (e.g. volume 5a).
See also
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