用hal库写一个复杂的功能

好的，我可以给你一个例子。假设你想要使用HAL库控制一个带有多个传感器和执行器的机器人，下面是一个实现机器人行走和避障的示例代码：

#include "stm32f4xx_hal.h"
#include <stdbool.h>

#define LEFT_MOTOR_PIN1 GPIO_PIN_0
#define LEFT_MOTOR_PIN2 GPIO_PIN_1
#define RIGHT_MOTOR_PIN1 GPIO_PIN_2
#define RIGHT_MOTOR_PIN2 GPIO_PIN_3

#define ULTRASONIC_TRIG_PIN GPIO_PIN_4
#define ULTRASONIC_ECHO_PIN GPIO_PIN_5

#define MOTOR_PWM_FREQUENCY 1000
#define MOTOR_PWM_PRESCALER 84
#define MOTOR_PWM_PERIOD 1000

#define ULTRASONIC_TIMEOUT 5000

TIM_HandleTypeDef htim2;
TIM_HandleTypeDef htim3;

GPIO_TypeDef* motor_port = GPIOA;
GPIO_TypeDef* ultrasonic_port = GPIOB;

void setup_motors(void)
{
  // enable clock for GPIOA and TIM2
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_TIM2_CLK_ENABLE();

  // configure GPIO pins for motor control
  GPIO_InitTypeDef GPIO_InitStruct;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Pin = LEFT_MOTOR_PIN1 | LEFT_MOTOR_PIN2 | RIGHT_MOTOR_PIN1 | RIGHT_MOTOR_PIN2;
  HAL_GPIO_Init(motor_port, &GPIO_InitStruct);

  // configure TIM2 for PWM output
  TIM_OC_InitTypeDef pwm_config;
  htim2.Instance = TIM2;
  htim2.Init.Prescaler = MOTOR_PWM_PRESCALER;
  htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim2.Init.Period = MOTOR_PWM_PERIOD - 1;
  htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  HAL_TIM_PWM_Init(&htim2);
  pwm_config.OCMode = TIM_OCMODE_PWM1;
  pwm_config.Pulse = 0;
  pwm_config.OCPolarity = TIM_OCPOLARITY_HIGH;
  pwm_config.OCFastMode = TIM_OCFAST_DISABLE;
  HAL_TIM_PWM_ConfigChannel(&htim2, &pwm_config, TIM_CHANNEL_1);
  HAL_TIM_PWM_ConfigChannel(&htim2, &pwm_config, TIM_CHANNEL_2);
  HAL_TIM_PWM_ConfigChannel(&htim2, &pwm_config, TIM_CHANNEL_3);
  HAL_TIM_PWM_ConfigChannel(&htim2, &pwm_config, TIM_CHANNEL_4);
  HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_1);
  HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_2);
  HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_3);
  HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_4);
}

void set_motor_speed(float left_speed, float right_speed)
{
  uint32_t left_pulse = (uint32_t)(MOTOR_PWM_PERIOD * left_speed);
  uint32_t right_pulse = (uint32_t)(MOTOR_PWM_PERIOD * right_speed);
  __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, left_pulse);
  __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_2, left_pulse);
  __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_3, right_pulse);
  __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_4, right_pulse);
}

bool obstacle_detected(void)
{
  // enable clock for GPIOB and TIM3
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_TIM3_CLK_ENABLE();

  // configure GPIO pins for ultrasonic sensor
  GPIO_InitTypeDef GPIO_InitStruct;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Pin = ULTRASONIC_TRIG_PIN;
  HAL_GPIO_Init(ultrasonic_port, &GPIO_InitStruct);
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pin = ULTRASONIC_ECHO_PIN;
  HAL_GPIO_Init(ultrasonic_port, &GPIO_InitStruct);

  // configure TIM3 for measuring pulse width
  TIM_IC_InitTypeDef ic_config;
  htim3.Instance = TIM3;
  htim3.Init.Prescaler = 84;
  htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim3.Init.Period = 0xFFFF;
  htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  HAL_TIM_IC_Init(&htim3);
  ic_config.ICPolarity = TIM_ICPOLARITY_RISING;
  ic_config.ICSelection = TIM_ICSELECTION_DIRECTTI;
  ic_config.ICPrescaler = TIM_ICPSC_DIV1;
  ic_config.ICFilter = 0;
  HAL_TIM_IC_ConfigChannel(&htim3, &ic_config, TIM_CHANNEL_1);
  HAL_TIM_IC_Start(&htim3, TIM_CHANNEL_1);

  // generate ultrasonic pulse
  HAL_GPIO_WritePin(ultrasonic_port, ULTRASONIC_TRIG_PIN, GPIO_PIN_SET);
  HAL_Delay(10);
  HAL_GPIO_WritePin(ultrasonic_port, ULTRASONIC_TRIG_PIN, GPIO_PIN_RESET);

  // wait for echo pulse to start
  uint32_t start_time = HAL_GetTick();
  while (HAL_GPIO_ReadPin(ultrasonic_port, ULTRASONIC_ECHO_PIN) == GPIO_PIN_RESET) {
    if (HAL_GetTick() - start_time > ULTRASONIC_TIMEOUT) {
      return false;
    }
  }

  // measure pulse duration
  start_time = HAL_GetTick();
  while (HAL_GPIO_ReadPin(ultrasonic_port, ULTRASONIC_ECHO_PIN) == GPIO_PIN_SET) {
    if (HAL_GetTick() - start_time > ULTRASONIC_TIMEOUT) {
      return false;
    }
  }
  uint32_t pulse_duration = HAL_TIM_ReadCapturedValue(&htim3, TIM_CHANNEL_1);
  float distance = (float)pulse_duration * 0.034 / 2;

  return distance < 30; // obstacle detected if distance is less than 30 cm
}

int main(void)
{
  HAL_Init();
  setup_motors();

  while (1) {
    bool obstacle = obstacle_detected();
    if (obstacle) {
      set_motor_speed(0, 0);
      HAL_Delay(1000);
      set_motor_speed(-0.5, 0.5); // turn left
      HAL_Delay(1000);
    } else {
      set_motor_speed(0.5, 0.5); // move forward
    }
  }
}

这个代码片段演示了如何使用HAL库来控制机器人的行动。其中包含了使用PWM输出控制电机速度，使用输入捕获测量超声波传感器的输出脉冲宽度等实现机器人避障功能的代码。