MIT Motor Controller Code Analyze

GitHub - bgkatz/motorcontrol: motor controller firmwareGitHub

Clock Tree

NVIC Settings

NVIC priority is configured in the code

HAL_NVIC_SetPriority(PWM_ISR, 0x0,0x0); // commutation > communication
HAL_NVIC_SetPriority(CAN_ISR, 0x01, 0x01);

PowerStage PWM Generation

Using DIV/1 prescaler, 0x8CA (2250) period, and center aligned mode -> PWM frequency is 80kHz

With the repetition counter set to 1, the software interrupt frequency is 40kHz.

It handles the motor phase inversion at the last stage, before issuing value to TIM.

Current Sampling

It's using 2 phase current shunt, and using blocking ADC call to sample current.

Encoder

It's using blocking encoder read/write.

Using this line to fence off too-fast CS pin control:

HAL_GPIO_WritePin(ENC_CS, GPIO_PIN_RESET ); 	// CS low
HAL_SPI_TransmitReceive(&ENC_SPI, (uint8_t*)encoder->spi_tx_buff, (uint8_t *)encoder->spi_rx_buff, 1, 100);
while( ENC_SPI.State == HAL_SPI_STATE_BUSY );  					// wait for transmission complete
HAL_GPIO_WritePin(ENC_CS, GPIO_PIN_SET ); 	// CS high

This shouldn't be necessary when using blocking SPI transaction mode...

The Commutation Loop

void TIM1_UP_TIM10_IRQHandler(void)
{
  /* USER CODE BEGIN TIM1_UP_TIM10_IRQn 0 */
	//HAL_GPIO_WritePin(LED, GPIO_PIN_SET );	// Useful for timing

	/* Sample ADCs */
	analog_sample(&controller);

	/* Sample position sensor */
	ps_sample(&comm_encoder, DT);

	/* Run Finite State Machine */
	run_fsm(&state);

	/* Check for CAN messages */
	can_tx_rx();

	/* increment loop count */
	controller.loop_count++;
	//HAL_GPIO_WritePin(LED, GPIO_PIN_RESET );

  /* USER CODE END TIM1_UP_TIM10_IRQn 0 */
  HAL_TIM_IRQHandler(&htim1);
  /* USER CODE BEGIN TIM1_UP_TIM10_IRQn 1 */
  /* USER CODE END TIM1_UP_TIM10_IRQn 1 */
}