Timer 8 issue in Cube IDE V1.5.0

[DWeb_2]

When generating Code for STM32H753IIKx I recently stumbled across unexpected behaviour in Cube IDE V1.5.0. I'm using the processor Pins PH13-PH15 in order to output a PWM Signal from the N-Outputs of Timer 8 (CH1N1-3). However no correlating signals were observed.

My timer initialization:

static void MX_TIM8_Init(void)
{
 
  /* USER CODE BEGIN TIM8_Init 0 */
 
  /* USER CODE END TIM8_Init 0 */
 
  TIM_MasterConfigTypeDef sMasterConfig = {0};
  TIM_OC_InitTypeDef sConfigOC = {0};
  TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig = {0};
 
  /* USER CODE BEGIN TIM8_Init 1 */
 
  /* USER CODE END TIM8_Init 1 */
  htim8.Instance = TIM8;
  htim8.Init.Prescaler = 2000-1;
  htim8.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim8.Init.Period = 255-1;
  htim8.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim8.Init.RepetitionCounter = 0;
  htim8.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
  if (HAL_TIM_PWM_Init(&htim8) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterOutputTrigger2 = TIM_TRGO2_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim8, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sConfigOC.OCMode = TIM_OCMODE_PWM1;
  sConfigOC.Pulse = 255-1;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
  sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
  sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
  sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
  if (HAL_TIM_PWM_ConfigChannel(&htim8, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_TIM_PWM_ConfigChannel(&htim8, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_TIM_PWM_ConfigChannel(&htim8, &sConfigOC, TIM_CHANNEL_3) != HAL_OK)
  {
    Error_Handler();
  }
  sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
  sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
  sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
  sBreakDeadTimeConfig.DeadTime = 0;
  sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
  sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
  sBreakDeadTimeConfig.BreakFilter = 0;
  sBreakDeadTimeConfig.Break2State = TIM_BREAK2_DISABLE;
  sBreakDeadTimeConfig.Break2Polarity = TIM_BREAK2POLARITY_HIGH;
  sBreakDeadTimeConfig.Break2Filter = 0;
  sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
  if (HAL_TIMEx_ConfigBreakDeadTime(&htim8, &sBreakDeadTimeConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM8_Init 2 */
 
  HAL_TIM_PWM_ConfigChannel(&htim8, &sConfigOC, TIM_CHANNEL_1);
  HAL_TIM_PWM_ConfigChannel(&htim8, &sConfigOC, TIM_CHANNEL_2);
  HAL_TIM_PWM_ConfigChannel(&htim8, &sConfigOC, TIM_CHANNEL_3);
 
  HAL_TIM_PWM_Start_DMA(&htim8, TIM_CHANNEL_1, (uint32_t*)&RGB_array[0], 1);
  HAL_TIM_PWM_Start_DMA(&htim8, TIM_CHANNEL_2, (uint32_t*)&RGB_array[1], 1);
  HAL_TIM_PWM_Start_DMA(&htim8, TIM_CHANNEL_3, (uint32_t*)&RGB_array[2], 1);
  /* USER CODE END TIM8_Init 2 */
  HAL_TIM_MspPostInit(&htim8);
 
}

Cube IDE Setting:

Further investigation showed, that registers for controlling the driver stage were not set accordingly in the peripheral. Only the complementary outputs of the PWM stage were enabled (CH1-3).

Writing to the registers manually later on (outside of the auto-generated codeblock) solved the issue:

htim8.Instance->CCER = (1UL << 2) | (1UL << 6) | (1UL << 10);

Is this a bug or are there underlying mechanics which I'm not realizing?

[DWeb_2]

Does no one have a clue?

[Tilen MAJERLE]

If I well catch, you want only negative or positive + negatiev to control 6 mosfets with dead time? If second, you ahve to enable them in CubeMX.

[DWeb_2]

The timer is not used for any kind of bridge,... where dead time would be required. We just have a PCB where a RGB LED is routed to the PWM Pins. R, G and B to one Timer channel Pin. Not a huge deal, but I was just wondering what might be wrong here.

[waclawek.jan]

/**
  * @brief  Enables or disables the TIM Capture Compare Channel xN.
  * @param  TIMx to select the TIM peripheral
  * @param  Channel: specifies the TIM Channel
  *          This parameter can be one of the following values:
  *            @arg TIM_Channel_1: TIM Channel 1
  *            @arg TIM_Channel_2: TIM Channel 2
  *            @arg TIM_Channel_3: TIM Channel 3
  * @param  ChannelNState: specifies the TIM Channel CCxNE bit new state.
  *          This parameter can be: TIM_CCxN_ENABLE or TIM_CCxN_Disable. 
  * @retval None
  */
static void TIM_CCxNChannelCmd(TIM_TypeDef* TIMx, uint32_t Channel, uint32_t ChannelNState)
{

That's quoting from STM32Cube_FW_H7_V1.3.0\Drivers\STM32H7xx_HAL_Driver\Src\stm32h7xx_hal_tim_ex.c . I don't Cube at all, so don't know if this can be somehow clicked in CubeMX.

JW