PORTS Forum

Ports and Interfaces => USB => Topic started by: vanweric on June 12, 2012, 03:33:33 pm

Title: What characters are legal within product / serial number descriptor strings?
Post by: vanweric on June 12, 2012, 03:33:33 pm

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?

Title: Re: What characters are legal within product / serial number descriptor strings?
Post by: Jan Axelson on June 12, 2012, 08:16:41 pm

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

Title: Re: What characters are legal within product / serial number descriptor strings?
Post by: Bret on June 13, 2012, 12:16:56 pm

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.

Title: Re: What characters are legal within product / serial number descriptor strings?
Post by: Jan Axelson on June 13, 2012, 12:36:43 pm

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

Title: how to access serial ports??
Post by: sshaamu2829 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

Title: Re: What characters are legal within product / serial number descriptor strings?
Post by: Jan Axelson on June 17, 2012, 11:42:23 pm

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

Jan

Title: Re: What characters are legal within product / serial number descriptor strings?
Post by: vanweric on July 06, 2012, 12:25:15 pm

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.