Method Init

src/SBC/DataTransfer.cpp:433–521

}

void DataTransfer::Init() noexcept
{
	// Initialise transfer ready pin
	SetPinMode(SbcTfrReadyPin, OUTPUT_LOW);

	// Allocate buffers in SBC mode
#if HAS_LWIP_NETWORKING
	// We are going try allocating the transfer buffer memory from the PBUF pool.
	// In SAME70 builds we are relying on the PBUF pool size being large enough to accommodate both transfer buffers, because they must be in non-cached RAM.
	InitAllocationFromPbufPool();				// we are not using a wired Ethernet interface on the Duet so we can use the PBUF pool memory
	{
		void *const mem = AllocateFromPbufPool(SbcTransferBufferSize);
# if SAME70
		rxBuffer = (char *)mem;					// we MUST allocate from the PBUF pool because we need the memory to be non-cached
# else
		rxBuffer = (mem != nullptr) ? (char *)mem : (char *)new uint32_t[(SbcTransferBufferSize + 3)/4];
# endif
	}
	{
		void *const mem = AllocateFromPbufPool(SbcTransferBufferSize);
# if SAME70
		txBuffer = (char *)mem;
# else
		txBuffer = (mem != nullptr) ? (char *)mem : (char *)new uint32_t[(SbcTransferBufferSize + 3)/4];
# endif
	}
#elif SAME70
# error Must allocate buffers from non-cached RAM
#else
	rxBuffer = (char *)new uint32_t[(SbcTransferBufferSize + 3)/4];
	txBuffer = (char *)new uint32_t[(SbcTransferBufferSize + 3)/4];
#endif

#if SAME5x
	// Initialize SPI
	for (Pin p : SbcSpiSercomPins)
	{
		SetPinFunction(p, SbcSpiSercomPinsMode);
	}

	Serial::EnableSercomClock(SbcSpiSercomNumber);
	spi_dma_disable();

	SbcSpiSercom->SPI.CTRLA.reg |= SERCOM_SPI_CTRLA_SWRST;
	while (SbcSpiSercom->SPI.SYNCBUSY.reg & SERCOM_SPI_SYNCBUSY_SWRST) { };
	SbcSpiSercom->SPI.CTRLA.reg = SERCOM_SPI_CTRLA_DIPO(3) | SERCOM_SPI_CTRLA_DOPO(0) | SERCOM_SPI_CTRLA_MODE(2);
	SbcSpiSercom->SPI.CTRLB.reg = SERCOM_SPI_CTRLB_RXEN | SERCOM_SPI_CTRLB_SSDE | SERCOM_SPI_CTRLB_PLOADEN;
	while (SbcSpiSercom->SPI.SYNCBUSY.reg & SERCOM_SPI_SYNCBUSY_MASK) { };
	SbcSpiSercom->SPI.CTRLC.reg = SERCOM_SPI_CTRLC_DATA32B;
#else
	// Initialize SPI
	SetPinFunction(APIN_SBC_SPI_MOSI, SBCPinPeriphMode);
	SetPinFunction(APIN_SBC_SPI_MISO, SBCPinPeriphMode);
	SetPinFunction(APIN_SBC_SPI_SCK, SBCPinPeriphMode);
	SetPinFunction(APIN_SBC_SPI_SS0, SBCPinPeriphMode);

	spi_enable_clock(SBC_SPI);
	spi_disable(SBC_SPI);