USBLib_SetURB (SWI &56340) — Sets values in a URB
R0 | Pointer to URB | ||||
R1 | bits to flag item to set
| ||||
R2 | used size (only used if bit 0 is set) | ||||
R3 | pointer to data (only used if bit 1 is set) | ||||
R4 | total size (only used if bit 2 is set) |
R0 - R4 | Preserved |
This call allows a driver to change fields in a URB without a driver directly accessing the URB structure. Its main use is to change the used size parameter to vary the amount of data sent in a transaction.
The total size parameter must only be used if the URB is pointing to external data.