pwm 驱动电机动不了。

发布于 2019-07-25 01:29:16 浏览：2315 订阅该版

```include <rtthread.h>
#include <rtdevice.h>

#define LED_PIN_NUM         59      /* LED PIN脚编号，查看驱动文件drv_gpio.c确定 PD12*/
#define PWM_DEV_NAME        "pwm4"  /* PWM设备名称 */
#define PWM_DEV_CHANNEL     1       /* PWM通道 */

struct rt_device_pwm *pwm_dev;      /* PWM设备句柄 */

static int pwm_led_sample(int argc, char *argv[])
{
    rt_uint32_t period, pulse, dir;

period = 5000000;    /* 周期为0.5ms，单位为纳秒ns */
    dir = 1;            /* PWM脉冲宽度值的增减方向 */
    pulse = 0;          /* PWM脉冲宽度值，单位为纳秒ns */

/* 设置LED引脚脚模式为输出 */
    rt_pin_mode(LED_PIN_NUM, PIN_MODE_OUTPUT);
    /* 拉高LED引脚 */
    rt_pin_write(LED_PIN_NUM, PIN_HIGH);
    
    /* 查找设备 */
    pwm_dev = (struct rt_device_pwm *)rt_device_find(PWM_DEV_NAME);
    if (pwm_dev == RT_NULL)
    {
        rt_kprintf("pwm sample run failed! can't find %s device!<br>", PWM_DEV_NAME);
        return RT_ERROR;
    }

/* 设置PWM周期和脉冲宽度默认值 */
    rt_pwm_set(pwm_dev, PWM_DEV_CHANNEL, period, pulse);
    /* 使能设备 */
    rt_pwm_enable(pwm_dev, PWM_DEV_CHANNEL);
    
    while (1)
    {
        rt_thread_mdelay(5000);
        if (dir)
        {
            pulse += 5000;      /* 从0值开始每次增加5000ns */
        }
        else
        {
            pulse -= 5000;      /* 从最大值开始每次减少5000ns */
        }
        if (pulse >= period)
        {
            dir = 0;
        }
        if (0 == pulse)
        {
            dir = 1;
        }

/* 设置PWM周期和脉冲宽度 */
        rt_pwm_set(pwm_dev, PWM_DEV_CHANNEL, period, pulse);
    }
}
/* 导出到 msh 命令列表中 */
MSH_CMD_EXPORT(pwm_led_sample, pwm sample);```
按这些参数 来驱动电机，为啥电机不动呢？使用pwm, 用的驱动板 ![四路电机.png](/uploads/201907/25/012744xzpovdx1py1323s3.png)
接线  电机控制1  正转，，pwm1 里面的外面的  都试着接pd12 的pwm 信号，发现没反应？