Objective Development Forums 2013-08-15T21:21:02+02:00 https://forums.obdev.at/app.php/feed/topic/8586 2013-08-15T21:21:02+02:00 2013-08-15T21:21:02+02:00 https://forums.obdev.at/viewtopic.php?t=8586&p=25699#p25699 <![CDATA[Re: HID read speed?]]> Sorry for the intrusion.

Statistics: Posted by 1.21Gigawatts — Thu Aug 15, 2013 9:21 pm

]]> 2013-08-15T18:18:21+02:00 2013-08-15T18:18:21+02:00 https://forums.obdev.at/viewtopic.php?t=8586&p=25698#p25698 <![CDATA[HID read speed?]]>

Code: 

PROGMEM const char usbHidReportDescriptor[24] = {
    0x05, 0x01,                    // USAGE_PAGE (Generic Desktop)
    0x09, 0x05,                    // USAGE (Game Pad)
    0xa1, 0x01,                    // COLLECTION (Application)
    0xa1, 0x00,                    //   COLLECTION (Physical)
    0x05, 0x01,                    //     USAGE_PAGE (Generic Desktop)
    0x09, 0x36,                    //     USAGE (Slider)
    0x15, 0x00,                    //     LOGICAL_MINIMUM (0)
    0x25, 0x7f,                    //     LOGICAL_MAXIMUM (127)
    0x75, 0x08,                    //     REPORT_SIZE (8)
    0x95, 0x01,                    //     REPORT_COUNT (1)
    0x81, 0x02,                    //     INPUT (Data,Var,Abs)
    0xc0,                          //     END_COLLECTION
    0xc0                           // END_COLLECTION
};

My problem is that this only seems to get read every 35mS or so, and I need to be able to go at least three times as fast. I tried this with a more complicated report descriptor (X & Y 2-byte axes and 8 buttons) and the speed was about the same.

I'm developing on win 7-64 (but will also have a Mac application). Is this a windows limitation, or maybe an HID limitation? Can I not send data over an HID interface faster than this? If not, I'll have to go to a much messier plan B, and whatever drivers that entails. I do like the HID interface, given the lack of drivers and the clean installation that allows.

Statistics: Posted by 1.21Gigawatts — Thu Aug 15, 2013 6:18 pm

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