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From: Walker, R. <Wal...@co...> - 2012-12-12 21:58:00
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Hi Tim,
Hi Tim
> Are you fetching descriptor type 7, or are you fetching string (type 3)
> descriptor number 7? Those are two different things. Rather than
> subvert the meaning of the actual OTHER_SPEED_CONFIGURATION descriptor...
I'm not sure. I know that the value we need is an ascii-encoded string, so I suspect it will be a string type. I've included the technical description from the data sheet, so that maybe the implementation will be obvious to someone more familiar with the USB protocol.
Currently the debug info that I need to access is described in the data sheet as:
2.3.5.17: String Descriptor for Other Speed Configuration String
offset field value in byte order
-------- ------- ------------------------------
0 bDescLength 0x4e
1 bDesciptorType 0x03
2 wLangID debug information encoded ascii string
The ascii string uses a base 32 ascii encoding which uses the characters from '@'-'O' to encode
the received optical power and some of the bit error rate registers.
Is this enough info to determine if libusb can recover this information? The data sheet is quite detailed, so I can probably find any other required information that might be needed.
I've got the device identified, with a valid handle and device structure. What functions would
I use next to access this information? If it helps, I can post the code I've written so far.
Thank you very much for your help!
--
Rick Walker
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