void processUsbSendQueue(UsbDevice* usbDevice) {
while(usbDevice->configured &&
!QUEUE_EMPTY(uint8_t, &usbDevice->sendQueue)) {
// Make sure the USB write is 100% complete before messing with this buffer
// after we copy the message into it - the Microchip library doesn't copy
// the data to its own internal buffer. See #171 for background on this
// issue.
if(!waitForHandle(usbDevice)) {
return;
}
int byteCount = 0;
while(!QUEUE_EMPTY(uint8_t, &usbDevice->sendQueue) && byteCount < 64) {
usbDevice->sendBuffer[byteCount++] = QUEUE_POP(uint8_t, &usbDevice->sendQueue);
}
int nextByteIndex = 0;
while(nextByteIndex < byteCount) {
if(!waitForHandle(usbDevice)) {
return;
}
int bytesToTransfer = min(USB_PACKET_SIZE, byteCount - nextByteIndex);
usbDevice->deviceToHostHandle = usbDevice->device.GenWrite(
usbDevice->inEndpoint, &usbDevice->sendBuffer[nextByteIndex], bytesToTransfer);
nextByteIndex += bytesToTransfer;
}
}
}
void processUsbSendQueue(UsbDevice* usbDevice) {
if(usbDevice->configured && vbusEnabled()) {
// if there's nothing attached to the analog input it floats at ~828, so
// if we're powering the board from micro-USB (and the jumper is going
// to 5v and not the analog input), this is still OK.
debug("USB no longer detected - marking unconfigured");
usbDevice->configured = false;
}
// Don't touch usbDevice->sendBuffer if there's still a pending transfer
if(!waitForHandle(usbDevice)) {
return;
}
while(usbDevice->configured &&
!QUEUE_EMPTY(uint8_t, &usbDevice->sendQueue)) {
int byteCount = 0;
while(!QUEUE_EMPTY(uint8_t, &usbDevice->sendQueue) &&
byteCount < USB_SEND_BUFFER_SIZE) {
usbDevice->sendBuffer[byteCount++] = QUEUE_POP(uint8_t,
&usbDevice->sendQueue);
}
int nextByteIndex = 0;
while(nextByteIndex < byteCount) {
// Make sure the USB write is 100% complete before messing with this
// buffer after we copy the message into it - the Microchip library
// doesn't copy the data to its own internal buffer. See #171 for
// background on this issue.
// TODO instead of dropping, replace POP above with a SNAPSHOT
// and POP off only exactly how many bytes were sent after the
// fact.
// TODO in order for this not to fail too often I had to increase
// the USB_HANDLE_MAX_WAIT_COUNT. that may be OK since now we have
// VBUS detection.
if(!waitForHandle(usbDevice)) {
debug("USB not responding in a timely fashion, dropped data");
return;
}
int bytesToTransfer = min(MAX_USB_PACKET_SIZE_BYTES,
byteCount - nextByteIndex);
usbDevice->deviceToHostHandle = usbDevice->device.GenWrite(
usbDevice->inEndpoint,
&usbDevice->sendBuffer[nextByteIndex], bytesToTransfer);
nextByteIndex += bytesToTransfer;
}
}
}
