Re: Usb cardreader returns strange values

[Peter S. <pe...@st...>]

Hi Donnovan,

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Donnovan Deekman wrote:
> I wrote an application for reading a usb cardreader using libusb. 
> When i pull the card true the magnet i get a lot of binary values,
> these values don't mach the values i get when i just use the
> cardreader as a keybord(using the original hid software of my pc).

That is because the cardreader is following the HID class for it's
communication. If you want, you can re-invent the HID class wheel, so
that you can parse the data in your application, instead of letting
the well-tested parser in the kernel do it.

I would recommend that you use HIDAPI rather than libusb for getting
the raw data, since this will work with less hassle across more
platforms.


> I see that a lot of people have the same problem but. does anyone
> have a solution to this problem.

What solution fits best basically depends on your environment and
your requirements, which you didn't mention, so it's difficult to
make some suggestions.


But in general, try to use the kernel HID implementation.


//Peter