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H3LIS200DL SPI Configuration & Read

Question asked by roofie01 on Jun 12, 2017
Latest reply on Jun 12, 2017 by roofie01


According to all the documentation I can find, I have configured the STM32F4 correctly to interface to the H3LIS200DL accelerometer. This is for use in SPI3 (AF6). Somehow, there's still something amiss. When I try to send/read the "WHO_AM_I" register, it only returns 0. Here's my setup code:


void configH3LIS200DL( void )
    GPIO_InitTypeDef GPIO_InitStructure;
    SPI_InitTypeDef  SPI_InitStructure;


    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC | RCC_AHB1Periph_GPIOD, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI3, ENABLE);


    //Initialize pins for SPI functionality
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11 | GPIO_Pin_12;
    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_NOPULL;
    GPIO_Init(GPIOC, &GPIO_InitStructure);
    //Initialize Chip Select pin
    GPIO_InitStructure.GPIO_Pin = ACCHI_CS;
    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(GPIOD, &GPIO_InitStructure);
    GPIO_SetPinHigh(GPIOD, ACCHI_CS);    


    GPIO_PinAFConfig (GPIOC, GPIO_Pin_10 | GPIO_Pin_11 | GPIO_Pin_12, GPIO_AF_SPI3);
    SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
    SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
    SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;
    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_32;
    SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
    SPI_InitStructure.SPI_CRCPolynomial = 0;
    SPI_Init(SPI3, &SPI_InitStructure);
    SPI_Cmd(SPI3, ENABLE);



//the function to send and receive

uint8_t SPI3_Send( uint16_t dataIn )
    GPIO_SetPinLow(GPIOD, GPIO_Pin_0);
    // write data to be transmitted to the SPI data register
    SPI3->DR = dataIn;
    // wait until transmit complete
    while( !(SPI3->SR & SPI_I2S_FLAG_TXE) );
    // wait until receive complete    
    while( !(SPI3->SR & SPI_I2S_FLAG_RXNE) );
    // wait until SPI is not busy anymore
    while( SPI3->SR & SPI_I2S_FLAG_BSY );
    GPIO_SetPinHigh(GPIOD, GPIO_Pin_0);        
    // return data from SPI3 register
    return SPI3->DR;


In main:

    uint16_t rtnValue = SPI3_Send( H3LIS200DL_WHO_AM_I );  //==0xF
    printf("value = %x\n", rtnValue);    

//I also tried a dummy byte after...still no go
    rtnValue = SPI3_Send( 0x00 );
    printf("value = %x\n", rtnValue);


I have tried both 8bit and 16bit, and changing the prescaler. I have confirmed the CS line is going Low/high. I have not done any checks on the data lines, but I have other SPI devices (FRAM) that are on SPI1 and they are working OK. CLK/MISO/MOSI are conected correctly.


Can someone explain why this would be happening? What could be the problem?


Thank you...