STM32H5 GPIO toggling performance

[Brussl]

I use STM32H562 and/or STM32H503 (nucleo board). When try in loop only this line:

while (1)

{

GPIOB->ODR ^= GPIO_PIN_6;  

}

The frequency on pin is only 12.5 mhz. I use external quartz 8mhz (and 24mhz on nucleo)

I config  to 250mhz (with build-in CubeMX ) :

void SystemClock_Config(void)

{

RCC_OscInitTypeDef RCC_OscInitStruct = {0};

RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

/** Configure the main internal regulator output voltage

*/

__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

/** Initializes the RCC Oscillators according to the specified parameters

* in the RCC_OscInitTypeDef structure.

*/

RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;

RCC_OscInitStruct.HSEState = RCC_HSE_ON;

RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;

RCC_OscInitStruct.PLL.PLLSource = RCC_PLL1_SOURCE_HSE;

RCC_OscInitStruct.PLL.PLLM = 2;

RCC_OscInitStruct.PLL.PLLN = 125;

RCC_OscInitStruct.PLL.PLLP = 2;

RCC_OscInitStruct.PLL.PLLQ = 2;

RCC_OscInitStruct.PLL.PLLR = 2;

RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_3;

RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1_VCORANGE_WIDE;

RCC_OscInitStruct.PLL.PLLFRACN = 0;

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_PLLCLK;

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_5) != HAL_OK)

{

Error_Handler();

}

}

Why is output frequency is too low ?. In assembler are no more 5 lines. So must be arround 50mhz.

[Peter BENSCH]

Welcome @Brussl, to the community!

well, a similar issue has already been discussed several times in the community, for example here.

Hope that helps?

Regards
/Peter

[AScha.3]

In my speed test on H563 at 250M core , i got

bsrr 4ns , +12ns ( while loop 8+4ns) =>  16ns total , so about 62MHz output at a pin, including the while loop.

But only if compiling with optimizer -O2 (or -Ofast) , these cpus are made to be fast only in cooperation with the optimized code.  So set the optimizer...

[Brussl]

Tnx a lot for fast answers. I see and other strange - when i add HAL_Delay(1)  in loop the period is not around 2ms but 4ms - 2 time slower !

AScha.3 - Tnx will check it. Can you send me  SystemClock_Config(void) function if is different from mine. And what source you have use? And what is VCC - 3.3V?

[AScha.3]

To check internal clk, you have a MCO output ! Enable it, select the clock to test and test on mco pin with scope (or counter ) . I did this at first ... never trust anything. :)

-> testing pll1q (100M) /10 here , 10M coming out.

+ here SystemClock_Config , just as cube puzzeled it together:

void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS_DIGITAL;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLL1_SOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 4;
  RCC_OscInitStruct.PLL.PLLN = 250;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 5;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_1;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1_VCORANGE_WIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 0;
  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_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;

cpu at 3v3 , source ...is on NUCLEO-H563ZI board...hse bypass , set :8MHz  .

[Tesla DeLorean]

The RMW is going to be inherently slow. It's compounded by the speed of the bus.

Do singular writes to BSRR to set a pin high or low.

If you need to toggle a pin use the TIM. Don't saturate the processor and bus.

For driving patterns use DMA from a buffer to the GPIO BSRR register.

[Brussl]

to AScha.3 : Sorry to say but problem still. Please try with external qaurtz to make 250mhz.

I can't.  I use CubeIDE 1.14.1 

For example on MB1814 board (STM32H503) with 24mhz quarz:

void SystemClock_Config(void)

{

RCC_OscInitTypeDef RCC_OscInitStruct = {0};

RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

/** Configure the main internal regulator output voltage

*/

__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

/** Initializes the RCC Oscillators according to the specified parameters

* in the RCC_OscInitTypeDef structure.

*/

RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;

RCC_OscInitStruct.HSEState = RCC_HSE_ON;

RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;

RCC_OscInitStruct.PLL.PLLSource = RCC_PLL1_SOURCE_HSE;

RCC_OscInitStruct.PLL.PLLM = 3;

RCC_OscInitStruct.PLL.PLLN = 62;

RCC_OscInitStruct.PLL.PLLP = 2;

RCC_OscInitStruct.PLL.PLLQ = 50;

RCC_OscInitStruct.PLL.PLLR = 2;

RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_3;

RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1_VCORANGE_WIDE;

RCC_OscInitStruct.PLL.PLLFRACN = 4096;

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_PLLCLK;

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_5) != HAL_OK)

{

Error_Handler();

}

HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_PLL1Q, RCC_MCODIV_1);

}

Max frequency is around 18mhz when use optimization by speed.

Interesting is that on MCO1 pin not signal !!

I try and on other custom board with STM32H562 and result is the same.

This is photos of clock config:

[Brussl]

Some one to help ? I can't start project 3 days. Just simple 250mhz setup i can't make with extarnal qartz. Where is f..ng problem. I use last lib of stm32H5 1.1.1. My be something in library  is not OK!? Why frequency a half of 250 mhz and why on MCO1 pin not signal ? I check frequency of quarts and is 24mhz. So my scope measuring ok.

I see when use HAL_Delay(1) that delay time is not 1 ms but 2ms. SUPER STRANGE !!!

[AScha.3]

So first : why on MCO1 pin not signal ? This cannot be...we dont allow! :)

set mco in Cube (?) ->

then set the mux:

and check : input is the real value on your board ? :

on my H563 nucleo : is 8MHz !

Now check mco1 output ...!

[Brussl]

I set only in cubeMX. Please measure frequency with HAL_Delay in loop. And if you have output from MCO1 too measure it. I have not output form MCO1. Please check which is your version of HAL. I use last one.1.1