stm32f103步进电机加减速

步进电机加减速控制需要使用定时器和中断来实现。以下是一个简单的示例代码，以控制单个步进电机为例：

#include "stm32f10x.h"

#define STEPPER_PORT GPIOA
#define STEPPER_PIN1 GPIO_Pin_0
#define STEPPER_PIN2 GPIO_Pin_1
#define STEPPER_PIN3 GPIO_Pin_2
#define STEPPER_PIN4 GPIO_Pin_3

#define DELAY_US 1000

int step = 0;
int dir = 1;

void TIM2_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
    {
        if (dir > 0)
        {
            switch (step)
            {
                case 0:
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
                case 1:
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
                case 2:
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
                case 3:
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
            }
        }
        else
        {
            switch (step)
            {
                case 0:
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
                case 1:
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
                case 2:
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
                case 3:
                    GPIO_SetBits(STEPPER_PORT, STEPPER_PIN1);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN2);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN3);
                    GPIO_ResetBits(STEPPER_PORT, STEPPER_PIN4);
                    break;
            }
        }

        step += dir;
        if (step > 3)
        {
            step = 0;
        }
        else if (step < 0)
        {
            step = 3;
        }

        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
    }
}

void delay_us(uint32_t us)
{
    uint32_t count = us * (SystemCoreClock / 1000000) / 5;
    while (count--);
}

int main(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

    GPIO_InitStructure.GPIO_Pin = STEPPER_PIN1 | STEPPER_PIN2 | STEPPER_PIN3 | STEPPER_PIN4;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(STEPPER_PORT, &GPIO_InitStructure);

    TIM_TimeBaseStructure.TIM_Period = 999;
    TIM_TimeBaseStructure.TIM_Prescaler = SystemCoreClock / 1000000 - 1;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    TIM_Cmd(TIM2, ENABLE);

    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    while (1)
    {
        for (int i = 0; i < 200; i++)
        {
            delay_us(DELAY_US);
        }

        dir = -dir;
    }
}

在这个示例中，步进电机使用四个引脚（PA0-PA3）来控制。使用定时器 TIM2 和中断来控制步进电机的脉冲信号。在中断处理程序中，根据步进电机的状态来切换引脚状态，以控制步进电机转动。在主循环中，通过改变 dir 的值来实现加减速的控制。可以通过适当调整 DELAY_US 的值来控制步进电机的速度。