[求助] 两块STM32F4之间spi握手通信问题

GPIO_InitTypeDef GPIO_InitStruct;

SPI_InitTypeDef SPI_InitStruct;

// enable clock for used IO pins

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

GPIO_InitStruct.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_4 | GPIO_Pin_3;

GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;

GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;

GPIO_Init(GPIOB, &GPIO_InitStruct);

// connect SPI1 pins to SPI alternate function

GPIO_PinAFConfig(GPIOB, GPIO_PinSource5, GPIO_AF_SPI1);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource4, GPIO_AF_SPI1);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource3, GPIO_AF_SPI1);

// enable peripheral clock

RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);

/* configure SPI1 in Mode 0

* CPOL = 0 --> clock is low when idle

* CPHA = 0 --> data is sampled at the first edge

*/

SPI_InitStruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex; // set to full duplex mode, seperate MOSI and MISO lines

SPI_InitStruct.SPI_Mode = SPI_Mode_Master; // transmit in master mode, NSS pin has to be always high

SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b; // one packet of data is 8 bits wide

SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low; // clock is low when idle

SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge; // data sampled at first edge

SPI_InitStruct.SPI_NSS = SPI_NSS_Soft | SPI_NSSInternalSoft_Set; // set the NSS management to internal and pull internal NSS high

SPI_InitStruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_16; // SPI frequency is APB2 frequency / 4

SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB;// data is transmitted MSB first

SPI_InitStruct.SPI_CRCPolynomial = 7;

SPI1->CR1 |=0x1000;

SPI1->CR2 |=0x20;

SPI_Init(SPI1, &SPI_InitStruct);

SPI_Cmd(SPI1, ENABLE); // enable SPI1

SPI1->DR = data; // write data to be transmitted to the SPI data register

while( !(SPI1->SR & SPI_I2S_FLAG_TXE) ); // wait until transmit complete

while( !(SPI1->SR & SPI_I2S_FLAG_RXNE) ); // wait until receive complete

while( SPI1->SR & SPI_I2S_FLAG_BSY ); // wait until SPI is not busy anymore

return SPI1->DR; // return received data from SPI data register

}

void init_SPI1(void){

GPIO_InitTypeDef GPIO_InitStruct;

SPI_InitTypeDef SPI_InitStruct;

// enable clock for used IO pins

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

GPIO_InitStruct.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_4 | GPIO_Pin_3;

GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;

GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;

GPIO_Init(GPIOB, &GPIO_InitStruct);

// connect SPI1 pins to SPI alternate function

GPIO_PinAFConfig(GPIOB, GPIO_PinSource3, GPIO_AF_SPI1);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource4, GPIO_AF_SPI1);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource5, GPIO_AF_SPI1);

// enable peripheral clock

RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);

/* configure SPI1 in Mode 0

* CPOL = 0 --> clock is low when idle

* CPHA = 0 --> data is sampled at the first edge

*/

SPI_InitStruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex; // set to full duplex mode, seperate MOSI and MISO lines

SPI_InitStruct.SPI_Mode = SPI_Mode_Slave; // transmit in master mode, NSS pin has to be always high

SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b; // one packet of data is 8 bits wide

SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low; // clock is low when idle

SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge; // data sampled at first edge

SPI_InitStruct.SPI_NSS = SPI_NSS_Soft; // set the NSS management to software

SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB;// data is transmitted MSB first

SPI_InitStruct.SPI_CRCPolynomial = 7;

SPI1->CR1 |=0x1000;

SPI1->CR2 |=0x20;

SPI_Init(SPI1, &SPI_InitStruct);

SPI_Cmd(SPI1, ENABLE); // enable SPI1

}

void SPI1_Send(uint8_t data){

SPI1->DR = data; // write data to be transmitted to the SPI data register

while( !(SPI1->SR & SPI_I2S_FLAG_TXE) ); // wait until transmit complete

}

uint8_t SPI1_Receive(void){

while( !(SPI1->SR & SPI_I2S_FLAG_RXNE) ); // wait until receive complete

return SPI1->DR; // return received data from SPI data register

}

while(1){

if(index_spi==BufferSize){

index_spi=0;

printf("%s\n\r",receive_data);

}

else{

receive_data[index_spi]=SPI1_Receive();

SPI1_Send(receive_data[index_spi]);

index_spi++;

}

for(index_data=0;index_data

receive_data[index_data]=SPI1_sendrecv(send_data[index_data]);

}

for(j=0;j<4;j++){

ack_string[j]=SPI1_sendrecv(0x00);

}

printf("%s\n\r",receive_data);

printf("ack string: %s\n\r",ack_string);

char ack_string[4]="GOOD";

while(1){

if(index_spi==BufferSize){

index_spi=0;

printf("%s\n\r",receive_data);

for(i=0;i<4;i++){

SPI1_Receive();

SPI1_Send(ack_string[i]);

}

}

else{

receive_data[index_spi]=SPI1_Receive();

SPI1_Send(receive_data[index_spi]);

index_spi++;

}

}