TraceBack (最近一次呼叫)和GPIO.setmode(GPIO.BOARD)或GPIO.setmode(GPIO.BCM)错误

Question

我一直在为一个脚本而苦苦挣扎，这个脚本将Pi的BCM引脚17，27和10打开1秒，然后关闭1秒，顺序大约100次。当我运行脚本时，LED1会打开，然后它会关闭，程序会关闭，并显示以下错误：

Traceback (most recent call last):
  File "LedBlink.py", line 47, in <module>
    LED2Blink()
  File "LedBlink.py", line 27, in LED2Blink
    GPIO.setup(LED2, GPIO.OUT)
RuntimeError: Please set pin numbering mode using     GPIO.setmode(GPIO.BOARD) or GPIO.setmode(GPIO.BCM)

import RPi.GPIO as GPIO
import time

LED1 = 17
LED2 = 27
LED3 = 10

GPIO.setmode(GPIO.BCM)

def LED1Blink():
        GPIO.setup(LED1, GPIO.OUT)
        GPIO.output(LED1,True) 
        time.sleep(1)  
        GPIO.output(LED1,False)
        time.sleep(1)
        GPIO.cleanup()

def LED2Blink():
        GPIO.setup(LED2, GPIO.OUT)
        GPIO.output(LED2,True) 
        time.sleep(1)  
        GPIO.output(LED2,False)
        time.sleep(1)
        GPIO.cleanup()

def LED3Blink():
        GPIO.setup(LED3, GPIO.OUT)
        GPIO.output(LED3,True) 
        time.sleep(1)  
        GPIO.output(LED3,False)
        time.sleep(1)
        GPIO.cleanup()

i = 0
while i < 100:
       LED1Blink()
       LED2Blink()
       LED3Blink()
       i + 1
else:
       print "finished loop"

Answer 1

问题是您在每个方法的末尾调用GPIO.cleanup()。如documentation中所述，您想要的是GPIO.cleanup(channel)，其中Note that GPIO.cleanup() also clears the pin numbering system in use.对应于脚本中的LED1, LED2, LED3。

最佳做法是仅设置一次和cleanup ，例如

import RPi.GPIO as GPIO
import time

LED1 = 17
LED2 = 27
LED3 = 10

GPIO.setmode(GPIO.BCM)
GPIO.setup(LED1, GPIO.OUT)
GPIO.setup(LED2, GPIO.OUT)
GPIO.setup(LED3, GPIO.OUT)

def LED1Blink():
        GPIO.output(LED1,True) 
        time.sleep(1)  
        GPIO.output(LED1,False)
        time.sleep(1)

def LED2Blink():
        GPIO.output(LED2,True) 
        time.sleep(1)  
        GPIO.output(LED2,False)
        time.sleep(1)

def LED3Blink():
        GPIO.output(LED3,True) 
        time.sleep(1)  
        GPIO.output(LED3,False)
        time.sleep(1)

i = 0
if i < 100:
       LED1Blink()
       LED2Blink()
       LED3Blink()
       i + 1
else:
       GPIO.cleanup()
       print "finished loop"

Answer 2

永远不要多次调用GPIO.cleanup()，因为在清除引脚的同时，它也会清除引脚模式！所以，如果你在程序之间调用了它，那么下一条语句的执行就不会有引脚模式，这会给出一个错误。TraceBack(最近呼叫时间)和GPIO.setmode(GPIO.BOARD)或GPIO.setmode(GPIO.BCM)错误

因此，如果满足某些条件，请始终在程序可能结束/中断的地方使用它。