Im currently working on stm32f103r8. Now i need to interface the adx345 through SPI in stm32 also i coded for this,issue im getting here is when the simulation is running the SS is not getting low it is always in high state.please notify my mistakes and correct it.
The following is my program,
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#include "stm32f10x.h"
#define BufferSize 7
uint8_t buffer [BufferSize];
unsigned int a=0;
SPI_InitTypeDef SPI_Structure;
int main()
{
// RCC->APB2ENR =0x00001005; //spi clock enabled and gpioa port and afioa enabled
RCC->APB2ENR |= RCC_APB2ENR_AFIOEN | RCC_APB2ENR_IOPAEN | RCC_APB2ENR_SPI1EN; //spi clock enabled and gpioa port and afioa enabled
GPIOA->CRL =0x00000000; // all bits of the a ports are cleared
/* spi bus no 1 is used ,so the port A pins PA4,PA5,PA6,PA7 are used for communincation
PA4 - used as chip select (CS) alternate function push pull
PA5 - used as SCLK alternate function push pull
PA6 - used as MISO INPUT PULLUP
PA7 - USED as MOSI alternate function push pull
*/
GPIOA->CRL |= GPIO_CRL_CNF7_1 | GPIO_CRL_CNF6_1 | GPIO_CRL_CNF5_1 |GPIO_CRL_CNF4_1 ; //config bits for 4,5,6,7
GPIOA->CRL |= GPIO_CRL_MODE7_1 | GPIO_CRL_MODE7_0 | GPIO_CRL_MODE5_1 | GPIO_CRL_MODE5_0 | GPIO_CRL_MODE4_1 | GPIO_CRL_MODE4_0; //MODE bits for 4,5,6,7
SPI_Structure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_Structure.SPI_Mode = SPI_Mode_Master;
SPI_Structure.SPI_DataSize = SPI_DataSize_8b;
SPI_Structure.SPI_CPOL = SPI_CPOL_High;
SPI_Structure.SPI_CPHA = SPI_CPHA_2Edge;
SPI_Structure.SPI_NSS = SPI_NSS_Soft;
SPI_Structure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;
SPI_Structure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_Structure.SPI_CRCPolynomial = 7;
SPI1->CR2 |=0x0004;
SPI_Init(SPI1, &SPI_Structure); //SPI initiated by SPI_Init func
SPI_CalculateCRC(SPI1, ENABLE);
SPI_Cmd(SPI1, ENABLE);
// SPI_I2S_SendData(SPI1,i);
// buffer[a++] = SPI_I2S_ReceiveData(SPI1);
while(1)
{
SPI_I2S_SendData(SPI1,0x2D);
for(int i=0;i<=10000;i++);
// SPI_TransmitCRC(SPI1);
}
//return 0;
}
