void SPIClass::begin() {
if(init_flag==0) init();
/* Unlock protected registers */
SYS_UnlockReg();
/* Enable IP clock */
CLK_EnableModuleClock(module);
/* Select IP clock source and clock divider */
CLK_SetModuleClock(module,clksel,0);
/* Lock protected registers */
SYS_LockReg();
/* Configure as a master, clock idle low, falling clock edge Tx, rising edge Rx and 8-bit transaction */
/* Set IP clock divider. SPI clock rate = 4MHz */
SPI_Open(spi, SPI_MASTER, SPI_MODE_0, 8, 4000000);
#if defined(__NUC240__) | defined(__NANO100__) | defined(__NUC131__)
SPI_EnableFIFO(spi,12,12);
#endif
setBitOrder(SS, MSBFIRST);
#if defined(__M451__)
SPI_ClearRxFIFO(spi);
SPI_TRIGGER(spi);
#endif
}
/* ------------- */
int main(void)
{
uint32_t u32DataCount;
/* Unlock protected registers */
SYS_UnlockReg();
/* Init system, IP clock and multi-function I/O. */
SYS_Init();
/* Lock protected registers */
SYS_LockReg();
/* Configure UART0: 115200, 8-bit word, no parity bit, 1 stop bit. */
UART_Open(UART0, 115200);
/* Init SPI */
SPI_Init();
printf("\n\n");
printf("+-----------------------------------------------------+\n");
printf("| SPI Master Mode Sample Code |\n");
printf("+-----------------------------------------------------+\n");
printf("\n");
printf("Configure SPI0 as a master.\n");
printf("Bit length of a transaction: 32\n");
printf("The I/O connection for SPI0:\n");
printf(" SPI0_SS0 (PC.0)\n SPI0_CLK (PC.1)\n");
printf(" SPI0_MISO0 (PC.2)\n SPI0_MOSI0 (PC.3)\n\n");
printf("SPI controller will enable FIFO mode and transfer %d data to a off-chip slave device.\n", TEST_COUNT);
printf("In the meanwhile the SPI controller will receive %d data from the off-chip slave device.\n", TEST_COUNT);
printf("After the transfer is done, the %d received data will be printed out.\n", TEST_COUNT);
printf("The SPI master configuration is ready.\n");
for(u32DataCount = 0; u32DataCount < TEST_COUNT; u32DataCount++)
{
/* Write the initial value to source buffer */
g_au32SourceData[u32DataCount] = 0x00550000 + u32DataCount;
/* Clear destination buffer */
g_au32DestinationData[u32DataCount] = 0;
}
printf("Before starting the data transfer, make sure the slave device is ready. Press any key to start the transfer.\n");
getchar();
printf("\n");
/* Set TX FIFO threshold, enable TX FIFO threshold interrupt and RX FIFO time-out interrupt */
SPI_EnableFIFO(SPI0, 4, 4);
SPI_EnableInt(SPI0, SPI_FIFO_TX_INT_MASK | SPI_FIFO_TIMEOUT_INT_MASK);
g_u32TxDataCount = 0;
g_u32RxDataCount = 0;
NVIC_EnableIRQ(SPI0_IRQn);
/* Wait for transfer done */
while(g_u32RxDataCount < TEST_COUNT);
/* Print the received data */
printf("Received data:\n");
for(u32DataCount = 0; u32DataCount < TEST_COUNT; u32DataCount++)
{
printf("%d:\t0x%X\n", u32DataCount, g_au32DestinationData[u32DataCount]);
}
/* Disable TX FIFO threshold interrupt and RX FIFO time-out interrupt */
SPI_DisableInt(SPI0, SPI_FIFO_TX_INT_MASK | SPI_FIFO_TIMEOUT_INT_MASK);
NVIC_DisableIRQ(SPI0_IRQn);
printf("The data transfer was done.\n");
printf("\n\nExit SPI driver sample code.\n");
/* Reset SPI0 */
SPI_Close(SPI0);
while(1);
}
