Appendix E. Development FAQ
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## Appendix E. Development FAQ

E.1. Does my application driver have to be started by the USB system?
E.2. How does my driver find unclaimed devices
E.3. If my driver waits for completion from module code teh transaction never completes.
E.4. Why does pressing Ctrl-Alt-F1 cause the USB Wimp application to quit?

E.1. | Does my application driver have to be started by the USB system?
| No. Any driver may be started at any time, the auto run mechanism is merely a convenient way for drivers to be automatically started when a device is inserted see Chapter 3 for more details on starting a driver.
E.2. | How does my driver find unclaimed devices
| The simplest way is to use USBLib_FindFreeDev (SWI &56340) see Chapter 3 for more details on starting a driver and locating devices.
E.3. | If my driver waits for completion from module code teh transaction never completes.
| This was an issue with callback starvation, it has been fixed in RC2.
E.4. | Why does pressing Ctrl-Alt-F1 cause the USB Wimp application to quit?
| This is caused by some versions of Strong Ed, the USB application was simply unfortunate, other applications may crash randomly also.

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