Posted on May 17, 2011 at 12:25#define DUMMY_BYTE 0xff
static unsigned char tx8(unsigned char data)
{
while ((SPI1->SR & SPI_FLAG_TXE) == (u16)RESET); // Loop while DR register in not emplty
SPI1->DR = data;
while ((SPI1->SR & SPI_FLAG_RXNE) == (u16)RESET); // Wait to receive a byte
return SPI1->DR;
}
void spi_tx_8 (unsigned char _data8)
{
tx8(_data8);
}
unsigned char spi_rx_8 (void)
{
return tx8(DUMMY_BYTE);
}
unsigned long spi_rx_32 (void)
{
unsigned long r;
int i;
for (i = 0,r = 0; i
{
r |= spi_rx_8();
if (i
r<<=8;
}
return r;
}
void spi_init (void)
{
SPI_InitTypeDef SPI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
/* Enable SPI1 and GPIOA clocks */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1 | RCC_APB2Periph_GPIOA, ENABLE);
/* Configure SPI1 pins: SCK(PA5), MISO(PA6) and MOSI(PA7) */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Configure PA.3 as Output push-pull, used as Flash Chip select */
/********* using pc.6 (LED1)
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
*/
/* Deselect the FLASH: Chip Select high */
DATAFLASH_CS_HI();
/* SPI1 configuration */
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
// SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_16;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPI1, &SPI_InitStructure);
/* Enable SPI1 */
SPI_Cmd(SPI1, ENABLE);
}
