B-LO72Z-LRWAN1 HAL_RNG

[GErma.1]

Hi

I am trying to generate a true random number on the B-LO72Z-LRWAN1 using the HAL_RNG_GenerateRandomNumber function with the code below:

uint32_t rnd_generator (void) {

RNG_HandleTypeDef RngHandle;  // RNG handler declaration 

uint32_t rv;

  RngHandle.Instance = RNG;

  if (HAL_RNG_Init(&RngHandle) != HAL_OK) {

    printf ("\n Error RNG_Init \n");

  }

  if (HAL_RNG_GenerateRandomNumber(&RngHandle, &rv) != HAL_OK) {

    printf ("\n Error RNG_Generate \n");

  }

  HAL_RNG_DeInit(&RngHandle);

  return rv;

}

The HAL_RNG_GenerateRandomNumber always returns an error and the generated number is always the same.

I believe that I must initialize the clock for the RND module using my own version of the HAL_RNG_MspInit and HAL_RNG_MspDeInit functions.

Can you provide me some help on this?

BR

Gilberto

[Tesla DeLorean]

STM32Cube_FW_L0_V1.11.0\Projects\NUCLEO-L073RZ\Examples\RNG\RNG_MultiRNG\Src\stm32l0xx_hal_msp.c

/**
 * @brief RNG MSP Initialization
 * This function configures the hardware resources used in this example:
 * - Peripheral's clock enable
 * @param hrng: RNG handle pointer
 * @retval None
 */
void HAL_RNG_MspInit(RNG_HandleTypeDef *hrng)
{
 
 RCC_OscInitTypeDef RCC_OscInitStruct = {0};
 RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
 
 /* Enable HSI48 Oscillator for USB/RNG */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
 RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
 if(HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 /* Initialization Error */
 while(1);
 }
 
 /* configure RNG clock for USB or RNG analog part */
 PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_USB;
 PeriphClkInitStruct.UsbClockSelection = RCC_USBCLKSOURCE_HSI48;
 if(HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct)!= HAL_OK)
 {
 /* Initialization Error */
 while(1);
 }
 
 /* RNG Peripheral clock enable */
 __HAL_RCC_RNG_CLK_ENABLE();
 
}
 
/**
 * @brief RNG MSP De-Initialization
 * This function freeze the hardware resources used in this example:
 * - Disable the Peripheral's clock
 * @param hrng: RNG handle pointer
 * @retval None
 */
void HAL_RNG_MspDeInit(RNG_HandleTypeDef *hrng)
{
 /* Enable RNG reset state */
 __HAL_RCC_RNG_FORCE_RESET();
 
 /* Release RNG from reset state */
 __HAL_RCC_RNG_RELEASE_RESET();
}