On Jul 5, 2007, at 7:11 PM, Washington Trindade wrote: > To read from the device is the same process, but I want to read > more than 8 > bytes, which is the max length of the packet. Then, I think I would > to do > many reads in a loop and concatenate the result in a buffer, but I > don't > know how to stop that loop? the hid_interrupt_read says when there > is no > more data?
The usual advice on the libusb lists is to request as many bytes as you want, and the kernel will break that up into individual requests of 8 bytes each. Then, you will get one buffer back with all of the bytes. However, I think that you will have to increase the timeout to account for this. hid_interrupt_read() will return HID_RET_FAIL_INT_READ if you request 8 bytes, and fewer than 8 are returned. This is not strictly an error in USB terms, but for actual USB HID requests, the interpretation of a short report is not defined. If the chip returns only 8-byte packets, then you can just loop until you get an error code. -- Charles Lepple _______________________________________________ libhid-discuss mailing list [email protected] http://lists.alioth.debian.org/mailman/listinfo/libhid-discuss
