Service_USB 1 (changes)
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Programmer's Reference Manuals
» Part 16 – Service Calls
» Service_USBDriver?Service_USB
» Service_USBDriver Service_USB 1
Service_USBDriver Service_USB 1
(Service &D2)
| Entry | |
|---|---|
| R0 | 1 |
| R1 | 210 (&D2) |
| R2 | 0 |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Preserved |
| R2 | Pointer to linked list of |
Use
This service is issued with OS_ServiceCall by any application or module which wishes to get information on all of the currently connected devices without needing to keep track of Attach (see Service_USBDriver 0?Service_USB 0 ) and Detach DeviceDead (SeeService_DeviceDead).
Notes
It is the responsibility of the issuer of the call to free the memory used by the returned descriptors in the RMA.
Each item in the linked list is created using OS_Module 6 and should be freed with OS_Module 7.
Do not claim this call, other USB drivers in the module chain may wish to add further blocks to the list.
See also
- OS_ServiceCall
- Service Calls
- Service_DeviceDead
Service_USBDriver?Service_USBService_USBDriver 0?Service_USB 0USBServiceCall Block?USB Service Call Block
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