Read data from USB device

Question

Im tring to read data from a USB device (USB camera that for some reason the CameraManager doesn't recognize). Ive asked for intent for intent and I can establish a connection with the device, but when i try to read data using bulkTransfer but it returns -1 each time.

This is the code for reading the data:

fun readat(): ByteArray {
    val buffer = ByteArray(endpoint.maxPacketSize)
    val result = m_connection?.bulkTransfer(endpoint, buffer, buffer.size, 6000)
    if (result!! < 0) {
        Log.i("serial", "The receive wasn't successful ")
    }
    return buffer.copyOf(result)
}

I also tried setting the DTR after establishing the connection as was suggested in some post i had seen:

            m_connection = manager.openDevice(m_device)
            var intf = m_device?.getInterface(0)!!
            endpoint = intf.getEndpoint(0)
            if (m_connection!!.claimInterface(intf, true)) {
                Log.i("serial", "The interface was claimed successfully")
            } else {
                Log.i("serial", "The interface could not be claimed")
            }
            m_connection!!.controlTransfer(0x21, 0x22, 0x1, 0, null, 0, 0);

Does anyone have any suggestion on how to fix it?

Read data from USB device

0 Answers0