Raspberry Pi RuntimeError：已为此 GPIO 通道启用冲突边缘检测

我正在遵循此处找到的教程：https://www.linkedin.com/pulse/prepare-your-raspberry-pi-work-aws-iot-kay-lerch

I have not even begun the internet part of it as I was having issues with the circuit. I wired my circuit just like it is shown in this diagram below using my raspberry pi 3.

然后我编写了以下 python 脚本，如教程中所示。

import RPi.GPIO as gpio

gpio.setmode(gpio.BOARD)
gpio.setup(7, gpio.IN, pull_up_down=gpio.PUD_DOWN)

def on_pushdown(channel):
        print "Button Pushed."

while(True):
        gpio.add_event_detect(7, gpio.RISING, callback=on_pushdown, bouncetime=200)
gpio.cleanup()

当我按下按钮时，这应该打印出“Button Pushed”，但出现以下运行时错误：

Traceback (most recent call last):
  File "button.py", line 10, in <module>
    gpio.add_event_detect(7, gpio.RISING, callback=on_pushdown, bouncetime=200)
RuntimeError: Conflicting edge detection already enabled for this GPIO channel

我有 RPi.GPIO 版本 0.6.2，这是撰写本文时的最新版本。我将不胜感激任何人可以提供的任何帮助。

您拥有的代码不断添加事件检测回调（在while(True)环形）。您想要的是添加一次事件检测回调，然后等待边缘。

This page有一个您可能想要了解的好例子。

或者，您可以尝试类似的方法：

import RPi.GPIO as gpio

gpio.setmode(gpio.BOARD)
gpio.setup(7, gpio.IN, pull_up_down=gpio.PUD_DOWN)

def on_pushdown(channel):
    print "Button Pushed."

# only add the detection call once!
gpio.add_event_detect(7, gpio.RISING, callback=on_pushdown, bouncetime=200)

while(True):
    try:
        # do any other processing, while waiting for the edge detection
        sleep(1) # sleep 1 sec
    finally:
        gpio.cleanup()