Force a Re-enumeration request

Discussions about USB Audio on XMOS devices
shaw
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Force a Re-enumeration request

Post by shaw »

We are developing a product based on USB Audio Reference software, version 8.1.0. We have a need to be able to update the connected PC with new device configuration information, after initial Power Up. Is there any way within the software to force a "Soft Disconnect" or "Soft Detach" to request that the PC initiate a re-enumeration request?. Thanks for any help.
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Ross
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Post by Ross »

The quickest way to do this would be the detach functionality already present in the DFU functionality, I should imagine.

What OS’s do you need to do this from?
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shaw
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Post by shaw »

primarily Windows. Maybe mac.
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Ross
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Post by Ross »

Are you licensing the Thesycon driver? Or using Windows built in? Asking because the host code will be slightly different.
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shaw
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Post by shaw »

licensing the Thesycon driver
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Ross
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Post by Ross »

The easiest was to achieve a detach/re-attach is to cause the device to reboot - this may or may not be acceptable based on product.

You could add a custom request to the device to do such a thing. However, using the standard DFU interface to move into DFU and then move back to application mode (i.e. two reboots) would give the desired functionality (I think..) without any code modifications or device or host. Just a thought.
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shaw
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Post by shaw »

What is the recommended way to initiate the reboot from within the XMOS code? (XU316-1024-FB265-C32 and v8.1.0 USB audio ref. code)
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Ross
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Post by Ross »

A write to the pll control register. Here's some example code: https://github.com/xmos/lib_xua/blob/de ... /reboot.xc
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shaw
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Post by shaw »

that did it, thank-you