Hello ALL,
I am using stm32f2xxx.
I am programing An accelerometer which is interfaced via SPI. The problem i m facing is the clock is not always continous. My HSEValue is 8Mhz.
When i get the clcok properly i could see RXNE flag and TXE flag set and it receives valid data. But when i dont get the clock properly i see only TXE flag set.
Below is my init, read and write codes
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA ,ENABLE);
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN;
_InitStructure.GPIO_Pin=SPI1_SCK_PIN;
GPIO_Init(SPI1_GPIO_PORT,&GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin=SPI1_MOSI_PIN;
GPIO_Init(SPI1_GPIO_PORT,&GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin=SPI1_MISO_PIN;
GPIO_Init(SPI1_GPIO_PORT,&GPIO_InitStructure);
GPIO_PinAFConfig(GPIOA,SPI1_SCK_SOURCE,GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA,SPI1_MOSI_SOURCE,GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA,SPI1_MISO_SOURCE,GPIO_AF_SPI1);
/*Configure CS pin in output pushpull mode*/
GPIO_InitStructure.GPIO_Pin = SPI1_CS_PIN;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(SPI1_GPIO_PORT, &GPIO_InitStructure);
}
void SPIConfiguration(void)
{
unsigned char ucdummy;
static char ucindex = 20;
unsigned char rxbuf[20];
void SPI_Config()
{
SPI_InitTypeDef SPI_InitStructure;
RCC_APB2PeriphClockCmd (RCC_APB2Periph_SPI1, ENABLE);
/*SPI initializations*/
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_2;
SPI_InitStructure.SPI_FirstBit=SPI_FirstBit_MSB;
//SPI_InitStructure.SPI_CRCPolynomial=7;
SPI_InitStructure.SPI_CRCPolynomial=0;
SPI_Init(SPI1,&SPI_InitStructure);
SPI_SSOutputCmd(SPI1,ENABLE);
SPI_Cmd(SPI1,ENABLE);
}
uint8_t SPIXLWriteData(uint8_t Add, uint16_t Data)
{
uint32_t TimeOut;
while ((SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_BSY)))
{
if (TimeOut--==0)
{
return SPI_ERROR;
}
}
CS_LOW();
SPI_I2S_SendData(SPI1, ADXL345_W|Add);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
ClrRcvBuf();
SPI_I2S_SendData(SPI1, Data);
ClrRcvBuf();
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_BSY) == SET);
CS_HIGH();
return 1;
}
uint8_t SPIReadData(uint8_t RegisterAddress, uint8_t NoOfRgisters)
{
uint32_t TimeOut;
uint16_t RxBuffer;
/* Select Slave*/
CS_LOW();
/*Make sure the bus is not busy*/
while ((SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_BSY)))
{
if (TimeOut--==0)
{
return SPI_TIMEOUT_ERROR;
}
}
//RxBuffer = SPI_I2S_ReceiveData(SPI1);
SPI_I2S_SendData(SPI1, XL345_R|RegisterAddress);
ClrRcvBuf();
RxBuffer=SPI_I2S_ReceiveData(SPI1);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
//dummy byte*/
SPI_I2S_SendData(SPI1, 0x00);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET); the
RxBuffer = SPI_I2S_ReceiveData(SPI1);
while(SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_TXE) != SET);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_BSY) == SET);
CS_HIGH();
return RxBuffer;
}
void SPIXLReadSequence(uint8_t reg,uint8_t count)
{
uint8_t i = 0;
CS_LOW();
SPI_I2S_SendData(SPI1, ADXL345_R | ADXL345_MB | reg);
ClrRcvBuf();
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
SPI_I2S_SendData(SPI1, 0xFF);
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_RXNE) == RESET);
data[i]= SPI_I2S_ReceiveData(SPI1);
i++;
}
while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_BSY) == SET);
CS_HIGH();
}
Could anyone help in resolving this issues
Thanks
