Author Topic: What characters are legal within product / serial number descriptor strings?  (Read 18082 times)

vanweric

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I recently encountered an HID device that malfunctions when the "`" character is in its Product descriptor string.  What characters are considered legal in these fields?

Jan Axelson

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Section 9.6.7 in the USB 2.0 says the characters are in Unicode, and string descriptor zero specifies the language.

Is the apostrophe 0027h or 2019h? Try the one you're not using.

Jan

Bret

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As far as I know, there are no characters that are "illegal" and can't be used in String Descriptors.  The only exceptions I know of are Serial Numbers, which should only use 0-9 and A-F.  If you're having a problem, I'd say it's an implementation issue with your software, not something that the device is doing incorrectly.

Somebody please correct me if I'm wrong, though.
« Last Edit: June 13, 2012, 12:20:07 pm by Bret »

Jan Axelson

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The serial number restriction is in the mass-storage bulk-only spec so in theory, other devices can use other characters in serial numbers.

Jan

sshaamu2829

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how to access serial ports??
« Reply #4 on: June 14, 2012, 01:57:21 am »
Hiii.I am unknown to the programming of serial ports..please suggest me something about how to access serial ports or usb ports,which language should i use or which tools should i use??
Also suggest me what should i do if i want to make a buzzer used in quiz competitions.thankyou

Jan Axelson

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At lvr.com, see these pages for example code and other links: serial ports, HID, winusb.

Jan

vanweric

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Just to follow up / close the thread:  The problem was in the device, it works just fine after we slapping the firmware guys around a bit.