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Who can help me with AVR-USB for HID?

Posted: Sun Oct 28, 2007 5:50 am
by sprhawk
I'm working with AVR-USB to make a customized Joystick with USB HID device.

Following many codes form Internet, I have made a code that can support only 1 (X/y/Z) axis, with the descriptor below:

Code: Select all

PROGMEM char usbHidReportDescriptor[26] = { /* USB report descriptor */
    0x05, 0x01,  // USAGE_PAGE (Generic Desktop)
    0x15, 0x00,  // LOGICAL_MINIMUM (0)
    0x09, 0x04,  // USAGE (Joystick)
    0xa1, 0x01,  // COLLECTION (Application)
    0x09, 0x01,  //   USAGE (Pointer)
    0xa1, 0x00,  //   COLLECTION (Physical)
    0x95, 0x01, //     REPORT_COUNT (1)
    0x75, 0x08, //     REPORT_SIZE (8)
    0x15, 0x0, //     LOGICAL_MINIMUM (-128)
    0x25, 0x7f, //     LOGICAL_MAXIMUM (127)
    0x09, 0x30,  //     USAGE (X)
//    0x09, 0x31,  //     USAGE (Y)
    0x81, 0x02,   //     INPUT (Data,Var,Abs)
    0xc0,  //     END_COLLECTION
    0xc0   // END_COLLECTION

};



When I try to add another axis, it fails(when programmed to Mega8, the USB detecting sound in Windows is quick three notes, and an Unkown Device is Identified):

Code: Select all

PROGMEM char usbHidReportDescriptor[28] = { /* USB report descriptor */
    0x05, 0x01, // USAGE_PAGE (Generic Desktop)
    0x09, 0x04,// USAGE (Joystick)
    0xa1, 0x01,  // COLLECTION (Application)
    0x05, 0x01, // USAGE_PAGE (Generic Desktop)
    0x09, 0x01,  //   USAGE (Pointer)
    0xa1, 0x00, //   COLLECTION (Physical)
    0x15, 0x81, //     LOGICAL_MINIMUM (-128)
    0x25, 0x7f, //     LOGICAL_MAXIMUM (127)
    0x75, 0x08,  //     REPORT_SIZE (8)
    0x95, 0x02,//     REPORT_COUNT (2)
    0x09, 0x30, //     USAGE (X)
    0x09, 0x31,  //     USAGE (Y)
    0x81, 0x02,  //     INPUT (Data,Var,Abs)
    0xc0,       //     END_COLLECTION
    0xc0   // END_COLLECTION
 };


I think the problem is on the descriptor, but i can't find the error.

I have changed the
Code:

Code: Select all

USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH


accordingly, and the right data buffer.

Who can tell me how to fix it?

When I changed the descriptor to 2 axes, I found the USB can't send correct data to PC, but why?

I found if i extend the X axis to 16bits ,the code can't workly properly too-- I mean it is indentified as Unknown Device.

Code: Select all

PROGMEM char usbHidReportDescriptor[29] = {
    0x05, 0x01,// USAGE_PAGE (Generic Desktop)
   0x15, 0x00,  // LOGICAL_MINIMUM (0)
    0x09, 0x04,// USAGE (Joystick)
    0xa1, 0x01,// COLLECTION (Application)
    0x05, 0x01,  // USAGE_PAGE (Generic Desktop)
    0x09, 0x01, //   USAGE (Pointer)
    0xa1, 0x00,//   COLLECTION (Physical)
    0x15, 0x0,//     LOGICAL_MINIMUM (0)
    0x26, 0xff,0x03, //     LOGICAL_MAXIMUM (1023)
    0x75, 0x10,  //     REPORT_SIZE (16)
   0x95, 0x01, //     REPORT_COUNT (1)
    0x09, 0x30,  //     USAGE (X)
    0x81, 0x02, //     INPUT (Data,Var,Abs)
   0xc0,  //     END_COLLECTION
    0xc0  // END_COLLECTION
};

OK, the bug is fixed, but I don't know why

Posted: Fri Nov 02, 2007 4:58 pm
by sprhawk
The bug has been fixed, I used a Mega16 board that is connected as MJoy16, the descriptior works. I don't know why.