Question
STM32L452 SystemClock_Config with STM32CubeMX
Posted on April 03, 2018 at 12:27
Hi,
I have Nuckeo-L452RE with STM32L452RE uC on board.
This uC max speed is 80MHz.
But after enabling MCO on pin PA8 in STM32CubeMX and generating the code to Atollic, I could see wrong SYSCLK frequencies.
The reason of this behavior is CubeMX generates wrong content of SystemClock_Config function:
/**Initializes the CPU, AHB and APB busses clocks
*/ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI; RCC_OscInitStruct.HSIState = RCC_HSI_ON; RCC_OscInitStruct.HSICalibrationValue = 16; RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON; RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;RCC_OscInitStruct.PLL.PLLN = 20; RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV7; RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2; RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV4;//...
It works fine after changing it to:
/**Initializes the CPU, AHB and APB busses clocks
*/ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI; RCC_OscInitStruct.HSIState = RCC_HSI_ON; RCC_OscInitStruct.HSICalibrationValue = 64; RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON; RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI; RCC_OscInitStruct.PLL.PLLM = 1; RCC_OscInitStruct.PLL.PLLN = 20; RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV7; RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2; RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV4;Best regards,
Mateusz
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