Solved
RTC is running extremely slowly (3 times too slow)
Hello.
I'm having a problem with an STM32H503.
I need to use the RTC, which is running on the internal 32kHz LSI clock.
The clock configuration was created with CubeMX.
When I check the RTC, I see that it has only advanced by 21 seconds in 60 seconds. That's a deviation of 285%.
The processor is running on the HSI clock, which is divided by 2, so 32MHz.
Does anyone know why the RTC is running 3 times too slow?
Init of the RCC:
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI | RCC_OSCILLATORTYPE_LSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV2;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.LSIState = RCC_LSI_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE; // RCC_PLL_OFF;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
| RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2
| RCC_CLOCKTYPE_PCLK3;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
{
Error_Handler();
}
Init of the RTC:
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127;
hrtc.Init.SynchPrediv = 999; // 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutPullUp = RTC_OUTPUT_PULLUP_NONE;
hrtc.Init.BinMode = RTC_BINARY_NONE;
if (HAL_RTC_Init(&hrtc) != HAL_OK)
{
Error_Handler();
}
privilegeState.rtcPrivilegeFull = RTC_PRIVILEGE_FULL_NO;
privilegeState.backupRegisterPrivZone = RTC_PRIVILEGE_BKUP_ZONE_NONE;
privilegeState.backupRegisterStartZone2 = RTC_BKP_DR0;
privilegeState.backupRegisterStartZone3 = RTC_BKP_DR0;
if (HAL_RTCEx_PrivilegeModeSet(&hrtc, &privilegeState) != HAL_OK)
{
Error_Handler();
}
/** Enable the WakeUp
* should be 100ms
*/
if (HAL_RTCEx_SetWakeUpTimer_IT(&hrtc, (100) , RTC_WAKEUPCLOCK_RTCCLK_DIV16, 0) != HAL_OK)
{
Error_Handler();
}