Posted on March 03, 2018 at 03:40The consequences of not initializing local/auto variables properly...
Original code:
static void SystemClock_Config(void)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_OscInitTypeDef RCC_OscInitStruct;
HAL_StatusTypeDef ret = HAL_OK;
/*
CORE=401060800, 401.06 MHz
CPUID 411FC271 DEVID 450 REVID 1001
Cortex M7 r1p1
C0000038 200017C0 00000000
10110221 12000011 00000040
FPU-D Single-precision and Double-precision
HCLK=200530400, 200.53 MHz
APB1=100265200, 100.27 MHz
APB2=100265200, 100.27 MHz
PLL1_Q_CK=200530400, 200.53 MHz
PLL2_R_CK=0, 0.00 MHz
480 x 272
*/
...
}
Modified code:
static void SystemClock_Config(void)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct
= {0};
RCC_OscInitTypeDef RCC_OscInitStruct
= {0};
HAL_StatusTypeDef ret = HAL_OK;
/*
CORE=400000000, 400.00 MHz
CPUID 411FC271 DEVID 450 REVID 1001
Cortex M7 r1p1
STM32H7xx
C0000038 200017C0 00000000
10110221 12000011 00000040
FPU-D Single-precision and Double-precision
HCLK=200000000, 200.00 MHz
APB1=100000000, 100.00 MHz
APB2=100000000, 100.00 MHz
PLL1_Q_CK=200000000, 200.00 MHz
PLL2_R_CK=0, 0.00 MHz
480 x 272
*/
...
}
The USART can recover from this, TIM might be marginally off frequency. Also has the potential to be unpredictable.
Here from
STM32Cube_FW_H7_V1.2.0\Projects\STM32H743I_EVAL\Applications\Display\LTDC_PicturesFromSDCard\Src\main.c
but systemic in the examples.
