کد:
//===================spi config=========================
GPIO_InitTypeDef gpio;
SPI_InitTypeDef spi;
RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOA | RCC_APB2Periph_SPI1, ENABLE );
// DAC CS PIN
gpio.GPIO_Pin =DAC1_CS_PIN|DAC2_CS_PIN|DAC3_CS_PIN;
gpio.GPIO_Mode =GPIO_Mode_Out_PP;
gpio.GPIO_Speed =GPIO_Speed_50MHz;
GPIO_Init(DAC_CS_PORT,&gpio);
// gpio.GPIO_Pin = GPIO_Pin_4;
// gpio.GPIO_Mode = GPIO_Mode_Out_PP;
// gpio.GPIO_Speed = GPIO_Speed_50MHz;
// GPIO_Init(GPIOA, &gpio);
gpio.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_7;
gpio.GPIO_Speed = GPIO_Speed_50MHz;
gpio.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOA, &gpio);
gpio.GPIO_Pin = GPIO_Pin_6;
gpio.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &gpio);
/* SPI configuration */
spi.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
spi.SPI_Mode = SPI_Mode_Master;
spi.SPI_DataSize = SPI_DataSize_8b;
spi.SPI_CPOL = SPI_CPOL_Low;
spi.SPI_CPHA = SPI_CPHA_1Edge;
spi.SPI_NSS = SPI_NSS_Soft;
spi.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_256; // 72000kHz/256=281kHz < 400kHz
spi.SPI_FirstBit = SPI_FirstBit_MSB;
spi.SPI_CRCPolynomial = 7;
SPI_Init(SPI1, &spi);
SPI_CalculateCRC(SPI1, DISABLE);
SPI_Cmd(SPI1, ENABLE);