我正在尝试通过 AWSIoT 点亮树莓派上的 LED,但我不断收到此错误
文件"mypub.py",第 71 行,在
GPIO.output(led21,GPIO.高(
连接返回结果:0
名称错误: 未定义名称"led21"
任何人都可以帮助解决这个问题吗?
我正在玩MQTT,试图点亮LED-s并最终与其他传感器进行交互。
我正在使用从这里获得的代码
# Publishes the Data to AWS IoT
import os
import socket
import ssl
import paho.mqtt.client as mqtt # Import the Paho-MQTT Client
from time import sleep # Import sleep from time for delays
import RPi.GPIO as GPIO # Import GPIO Library for Raspberry Pi
connection_flag = False # Initialize the Connection Flag as False
GPIO.setmode(GPIO.BCM) # Set Mode of RPi Pins i.e Broadcom or Chipset
# Define LED
led = 21 # Put LED Numbers
# Set Pin as Output
GPIO.setup( led, GPIO.OUT ) # Pin 21
GPIO.output(led, GPIO.LOW ) # Initialize LED's
def on_connect(client, userdata, flags, rc): # on_connect()-Event handler
global connection_flag # global to check if the Connection to AWS Cloud has been Made.
connection_flag = True
print( "Connection returned result: " + str( rc ) )
def on_message(client, userdata, msg): # on_message()-Event handler
print( msg.topic + " " + str( msg.payload ) )
mqttc = mqtt.Client() # Initiate Paho-MQTT Client
mqttc.on_connect = on_connect # .set on_connect Event handler
mqttc.on_message = on_message # .set on_message
# Define the AWS Host Key ; Thing Name defined in AWS IoT; Root Certificate Path; Certificate Path; Private Key Certificate Path
awshost = "xxxxxxxxxxxxxxxxxxxxxxxxxxx"
awsport = 8883 # AWS Port( Default: 8883 )
clientId = "raspberrypi" # Client ID
thingName = "raspberrypi" # Thing Name defined in AWS IoT
caPath = "root-CA.crt" # Root Certificate Path
certPath = "raspberrypi.cert.pem" # Certificate Path
keyPath = "raspberrypi.private.key" # Private Key Certificate Path
# Configure network encryption and authentication options
# Enable SSL/TLS support
mqttc.tls_set(caPath, certfile=certPath, keyfile=keyPath, cert_reqs=ssl.CERT_REQUIRED, tls_version=ssl.PROTOCOL_TLSv1_2, ciphers=None)
mqttc.connect(awshost, awsport, keepalive=60) # Connect to AWS Host
mqttc.loop_start()
while True:
if connection_flag == True:
GPIO.output( led21, GPIO.HIGH )
# Update LED Data on AWS IoT in Real Time
# State tells the current and previous state of LED
# Reported gives the timestamp
jsonMessage = "{ "state": { "reported": { "Led": " + str(state) + "} } }"
mqttc.publish( "$aws/things/raspberrypi/shadow/update",
jsonMessage,
qos = 1
)
mqttc.publish( "LED: ", # Publish the Data to AWS IOT and get it on Subscription
state,
qos = 1
)
print( "LED: " + "%d" % state )
sleep( 1.0 )
GPIO.output( led21, GPIO.HIGH ) # Update LED Data on AWS IoT in Real Time
jsonMessage = "{ "state": { "reported": { "Led": " + str(state) + "} } }"
mqttc.publish( "$aws/things/raspberrypi/shadow/update",
jsonMessage,
qos = 1
)
sleep( 1.0 )
mqttc.publish( "LED: ", # Publish the Data to AWS IOT and get it on Subscription
state,
qos = 1
)
print( "LED: " + "%d" % state )
else:
print( "Waiting for Connection..." )
ser.close()
GPIO.cleanup()
简单:
您的初始设置与符号led
相关联,而不是led21
...
# Define LED
# Put LED Numbers
led = 21
而代码的后面部分使用了未定义的符号led21
GPIO.output( led21, GPIO.HIGH )
替换名称以使其变得"连贯",瞧... :o(