void main_vendor_iso_out_received(udd_ep_status_t status,
iram_size_t nb_transfered, udd_ep_id_t ep)
{
uint8_t *buf_ptr;
UNUSED(ep);
if (UDD_EP_TRANSFER_OK != status) {
return; // Transfer aborted, then stop loopback
}
if (nb_transfered) {
ui_loop_back_state(true);
// Send on IN endpoint the data received on endpoint OUT
buf_ptr = &main_buf_loopback[ main_buf_iso_sel
*(sizeof(main_buf_loopback)/2) ];
udi_vendor_iso_in_run(
buf_ptr,
nb_transfered,
main_vendor_iso_in_received);
}
// Switch of buffer
main_buf_iso_sel = main_buf_iso_sel? 0:1;
// Immediately enable a transfer on next USB isochronous OUT packet
// to avoid to skip a USB packet.
// NOTE:
// Here the expected buffer size is equal to endpoint size.
// Thus, this transfer request will end after reception of
// one USB packet.
//
// When using buffer size larger than endpoint size,
// the requested transfer is stopped when the buffer is = full*.
// *on USBC and XMEGA USB driver, the buffer is full
// when "number of data transfered" > "buffer size" - "endpoint size".
buf_ptr = &main_buf_loopback[ main_buf_iso_sel
*(sizeof(main_buf_loopback)/2) ];
// Send on IN endpoint the data received on endpoint OUT
udi_vendor_iso_out_run(
buf_ptr,
udd_is_high_speed()?
UDI_VENDOR_EPS_SIZE_ISO_HS:UDI_VENDOR_EPS_SIZE_ISO_FS,
main_vendor_iso_out_received);
}
void usb_iso_received()
{
// Byte 0-3: First packet control bits (0xAAAAAAAA)
// Byte 4-5: Scanning speed in pps (big endian)
// Byte 6-7: Size of frame in points (big endian)
// Byte 8-X: Point data
// Each point: 8 MSB of x, 4 LSB of x + 4 MSB of y, 8 LSB of y, r, g, b, i (7 bytes total)
// Byte X-4: Last packet control bits (0xBBBBBBBB)
uint8_t* data = usbIsoBufferAddress;
bool processPacket = false;
bool lastPacket = false;
uint8_t intraFramePos = 0;
if (!newFrameReady)
{
//if control bits indicate first packet in frame
if ( (data[0] == 0xAA) &&
(data[1] == 0xAA) &&
(data[2] == 0xAA) &&
(data[3] == 0xAA) )
{
outputSpeed = ( (data[4] << 8) + data[5] );
newFrameSize = ( ((data[6] << 8) + data[7]) * 7 + 4);
if ((outputSpeed > MAXSPEED) || (outputSpeed < MINSPEED))
{
//error: wrong speed
}
else if (newFrameSize > MAXFRAMESIZE)
{
//error: wrong size
}
else
{
intraFramePos = 8;
newFramePos = 0;
processPacket = true;
}
}
else if (newFramePos != 0)
{
processPacket = true;
}
}
if (processPacket)
{
uint16_t bytesToCopy = 512 - intraFramePos;
//if last packet in frame expected
if ( (newFrameSize - newFramePos) <= bytesToCopy )
{
//adjust copy size and position
bytesToCopy = newFrameSize - newFramePos;
lastPacket = true;
}
//TODO copy data, below works?
memcpy(&newFrameAddress[newFramePos], &data[intraFramePos], bytesToCopy);
newFramePos += bytesToCopy;
//if last packet in frame expected
if (lastPacket)
{
//if control bytes indicates last packet in frame
uint8_t* frameEnd = newFrameAddress+newFrameSize;
if ( ( *(frameEnd-0) == 0xBB) &&
( *(frameEnd-1) == 0xBB) &&
( *(frameEnd-2) == 0xBB) &&
( *(frameEnd-3) == 0xBB) )
{
//frame successfully received
newFrameReady = true;
if (!playing)
{
playing = true;
speed_set(outputSpeed);
}
}
else
{
//faulty frame, discard
newFramePos = 0;
}
}
}
udi_vendor_iso_out_run(usbIsoBufferAddress, 512, usb_iso_received);
}
int callback_vendor_enable(void)
{
start();
udi_vendor_iso_out_run(usbIsoBufferAddress, 512, usb_iso_received);
return 1;
}
