Python串行數據解碼

Question

我通過以下python程序讀取串行數據。

import serial
import time
ser = serial.Serial('COM1', 9600, timeout=0)

var = '\x11\x02\x01\x00\xEC'
ser.write(var)
time.sleep(1)
while True:
try:
   Data_in = ser.readline().encode('hex')
   DF1 = Data_in [6:8]
   DF2 = Data_in [8:10]
   CO2 = int(DF1, 16)*256 + int(DF2, 16)
   print "=========================="
      print "Found Packet: " + Data_in
      print "DF 1: " + DF1 + " DF2: " + DF2 + " | CO2 : " + CO2
      time.sleep(1)
   except ser.SerialTimeoutException:
      print('Data could not be read')

輸出成功返回，但二氧化碳除外：

• 數據輸入：160b01072f000601bb02fb0041a8
• DF1：07
• DF2：2f

如果我想通過以下公式計算數據，則python程序返回錯誤。

CO2 = int（DF1，16）* 256 + int（DF2，16）

錯誤回溯（最近一次呼叫最近）：文件“ C：\\ Users \\ UserPC \\ workspace \\ aqi \\ testserialv1.py”，第40行，除了ser.SerialTimeoutException：AttributeError：'Serial'對象沒有屬性'SerialTimeoutException'

Answer 1

感謝您對CivFan的評論。 我將代碼修改為

 serial.SerialTimeoutException

它工作正常。 這是完整的代碼

import serial
import time

ser = serial.Serial('COM1', 9600, timeout=0)
var = '\x11\x02\x01\x00\xEC'

while True:
  try:
    ser.write(var)
    time.sleep(1)
    Data_in = ser.readline().encode('hex')
    print "=========================="
    print "Found Packet: " + Data_in

    Data_length = int( Data_in [2:4], 16)
    if Data_length == 11:
        DF1 = int( Data_in [6:8], 16)
        DF2 = int( Data_in [8:10], 16)
        CO2 = DF1*256.0 + DF2

        DF3 = int( Data_in [10:12], 16)
        DF4 = int( Data_in [12:14], 16)
        VOC = (DF3* 256 + DF4) / 100.0

        DF5 = int( Data_in [14:16], 16 )
        DF6 = int( Data_in [16:18], 16 )
        RH = (DF5*256.0 + DF6) / 10.0

        DF7 = int( Data_in [18:20], 16)
        DF8 = int( Data_in [20:22], 16)
        Temp = (DF7*256.0 + DF8-500) / 10.0

        DF9 = int( Data_in [22:24], 16)
        DF10 = int( Data_in [24:26], 16)
        PM25 = DF9*256.0 + DF10

        print "CO2 : " + str(CO2) + " VOC : " + str(VOC) + " RH : " + str(RH) + " Temp : " + str(Temp) + " PM : " + str(PM25)
        time.sleep(5)
except serial.SerialTimeoutException:
    print('Data could not be read')