STM32L4 - SPI2 clocking issue - c

Question

I am currently working on the STM32L476RG Nucleo board and I am trying to communicate with the SPI2 bus.
It seems that I am sending data with the MOSI pin but I don't have anything on the SCK pin.
Here are my initialisation code and sending data code:
In the main.c:
/Function that initializes the SPI/
void MX_SPI2_Init(void)
{
hspi2.Instance = SPI2;
hspi2.Init.Mode = SPI_MODE_MASTER;
hspi2.Init.Direction = SPI_DIRECTION_2LINES;
hspi2.Init.DataSize = SPI_DATASIZE_8BIT;
hspi2.Init.CLKPolarity = SPI_POLARITY_LOW;
hspi2.Init.CLKPhase = SPI_PHASE_1EDGE;
hspi2.Init.NSS = SPI_NSS_SOFT;
hspi2.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_16;
hspi2.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi2.Init.TIMode = SPI_TIMODE_DISABLED;
hspi2.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLED;
hspi2.Init.CRCPolynomial = 7;
hspi2.Init.CRCLength = SPI_CRC_LENGTH_DATASIZE;
hspi2.Init.NSSPMode = SPI_NSS_PULSE_DISABLED;
HAL_SPI_Init(&hspi2);
}
/Function that sends data via SPI to the slave/
void ADAS1000_SetRegisterValue(unsigned char regAddress,
unsigned long regVal)
{
unsigned char writeCmd[4] = {0, 0, 0, 0};
writeCmd[0] = 0x80 + regAddress; // Write bit and register address.
writeCmd[1] = (unsigned char)((regVal & 0xFF0000) >> 16);
writeCmd[2] = (unsigned char)((regVal & 0x00FF00) >> 8);
writeCmd[3] = (unsigned char)((regVal & 0x0000FF) >> 0);
HAL_SPI_Transmit(&hspi2, &(writeCmd[0]), (uint16_t) sizeof(writeCmd[0]), 50);
HAL_Delay(500);
HAL_SPI_Transmit(&hspi2, &(writeCmd[1]), (uint16_t) sizeof(writeCmd[1]), 50);
HAL_Delay(500);
HAL_SPI_Transmit(&hspi2, &(writeCmd[2]), (uint16_t) sizeof(writeCmd[2]), 50);
HAL_Delay(500);
HAL_SPI_Transmit(&hspi2, &(writeCmd[3]), (uint16_t) sizeof(writeCmd[3]), 50);
HAL_Delay(500);
}
In the hal_msp.c :
void HAL_SPI_MspInit(SPI_HandleTypeDef* hspi)
{
GPIO_InitTypeDef GPIO_InitStruct;
if(hspi->Instance==SPI2)
{
/* Peripheral clock enable */
__SPI2_CLK_ENABLE();
/**SPI2 GPIO Configuration
PC2 ------> SPI2_MISO
PC3 ------> SPI2_MOSI
PB10 ------> SPI2_SCK
PB12 ------> SPI2_NSS
*/
GPIO_InitStruct.Pin = GPIO_PIN_2|GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_MEDIUM;
GPIO_InitStruct.Alternate = GPIO_AF5_SPI2;
HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
GPIO_InitStruct.Pin = GPIO_PIN_10|GPIO_PIN_12;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_MEDIUM;
GPIO_InitStruct.Alternate = GPIO_AF5_SPI2;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
}
If you have any ideas or advice, thanks for helping!
EDIT
void MX_GPIO_Init(void)
{
/* GPIO Ports Clock Enable */
__GPIOC_CLK_ENABLE();
__GPIOA_CLK_ENABLE();
__GPIOB_CLK_ENABLE();
}

Answer 1

This might be the problem:
// [...]
hspi2.Init.NSS = SPI_NSS_SOFT;
// [...]
Without checking the definition of your HAL macros, I believe that this configures the SPI not to drive NSS - but to have this done by software. This means that you are responsible to assert the NSS pin manually before putting data into the SPI peripheral.
This in turn may cause the SPI slave side not to respond, which may appear like the SCK signals weren't reaching the slave at all.