SOLVED: How to send mulitple reports over one interrupt endp

[frampy]

I've been building a USB joystick controller for use in an arcade machine using V-USB. I've setup my report descriptor to contain two different reports using the REPORT_ID field (one for each player on tha machine).

I can send a report for each of the players individually, like so.

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if (TCNT0 > 47)  //47 == 4ms approx
{
    if (usbInterruptIsReady())
    {
        // this works fine, but only send a report for player 1
        buildReport(&gamepads[0], reportBuffer);
        usbSetInterrupt(reportBuffer, REPORT_SIZE);
    }
}

But I cannot send both reports squentially, I found some example code at http://www.raphnet.net/electronique/2ne ... dex_en.php which I've used to template this, but it doesn't work for me. Reference the following code sample, after usbSetInterrupt() is called, the code enters a loop waiting for the buffer to clear so we can set another interrupt, but the code gets stuck in this loop and never returns.

Someone help please! Programmer in peril.

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if (TCNT0 > 47) //47 == 4ms approx
{
    TCNT0 = 0;
    for (gp = 0; gp < NUM_GAMEPADS; gp++)
    {
        buildReport(&gamepads[gp], reportBuffer);
        if (usbInterruptIsReady())
        {
            usbSetInterrupt(reportBuffer, REPORT_SIZE);
            while (!usbInterruptIsReady())
            {
                // code hangs in this loop
                usbPoll();
                wdt_reset();

                // when uncommented, this toggles furiously!
                //toggle_pin();
            }
        }
    }
    // never see this toggled
    toggle_pin();
}

Thanks for your time

--Mike

[frampy]

I figured out why the code gets stuck in the loop waiting for usbInterruptIsReady() to return true.

The OS I'm using (Linux) won't poll the USB device unless there is a program actually using the device. In my case I'm running the following command to poll the device.

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jstest --event /dev/input/js0

Which polls the device just fine.

I was also able to reduce USB_CFG_INTR_POLL_INTERVAL to 2ms (not tested on windows).

I managed to get the two reports sending successfully using the following code. - this is mostly inspired by code found on raphnet.net

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    uint8_t must_report = 0;
    while(1) {

        wdt_reset();
        usbPoll(); //this must be called approx every 50ms

        pollButtons(&must_report);

        if (must_report) {
            for (gp = 0; gp < NUM_GAMEPADS; gp++) {
                if (must_report & (1 << gp) == 0)
                    continue;

                if (usbInterruptIsReady()) {
                    buildReport(&gamepads[gp], reportBuffer);
                    usbSetInterrupt(reportBuffer, REPORT_SIZE);
                    must_report &= ~(1 << gp);

                    while (!usbInterruptIsReady()) {
                        usbPoll();
                        wdt_reset();
                        pollButtons(&must_report);
                    }
                }
            }
        }
    }

[ulao]

its been understood for a long time that Linux will not work with mutiple descriptor reports like that, are you saying you over came that?

like this for example.
viewtopic.php?f=8&t=2926&p=9925&hilit=multi+linux#p9925