树莓派 --- 控制舵机转动代码Python

import time
import RPi.GPIO as GPIO
# 设置模式
GPIO.setmode(GPIO.BCM)
# 设置端口号
GPIO.setup(21, GPIO.OUT)

p = GPIO.PWM(21, 50)  # channel=12 frequency=50Hz
p.start(0)
try:
    while 1:
        for dc in range(0, 101, 5):
            p.ChangeDutyCycle(dc)
            time.sleep(0.1)
        for dc in range(100, -1, -5):
            p.ChangeDutyCycle(dc)
            time.sleep(0.1)
except KeyboardInterrupt:
    pass
p.stop()
GPIO.cleanup()