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SPI pins initialization STM32L-discovery

Question asked by JPetersen on Oct 8, 2012
Latest reply on Mar 19, 2013 by Clive One
It seems I can't correctly initialize the SPI pins on the STM32L-discovery board. I have very little experience with programming 32bit devices so I am probably missing something obvious. I hooked up my oscilloscope and the pins all go and stay high. My configuration code:

//Enable clock of the SPI module
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);

  /* Enable SCK, MOSI and MISO GPIO clocks */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);

  GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource12, GPIO_AF_SPI1);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource11, GPIO_AF_SPI1);

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_DOWN;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;

  /* SPI SCK pin configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  /* SPI  MOSI pin configuration */
  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_12;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  /* SPI MISO pin configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
  GPIO_Init(GPIOA, &GPIO_InitStructure);


  // Configure the SPI module
  SPI_InitTypeDef  SPI_InitStructure;
  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_64;
  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
  SPI_InitStructure.SPI_CRCPolynomial = 7;
  SPI_Init(SPI1, &SPI_InitStructure);
  SPI_Cmd(SPI1, ENABLE);           /* Enable the SPI  */

  /* Configure the Priority Group to 1 bit */
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);

  /* Configure the SPI interrupt priority */
  NVIC_InitTypeDef NVIC_InitStructure;
  NVIC_InitStructure.NVIC_IRQChannel = SPI1_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

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