import socket

import serial

import os

import sys

import struct

#serial

ser_intf = serial.Serial(port='/dev/ttyS0',baudrate=19200,bytesize=8,timeout=1)

#read data from power board serial port

def serialRead(serial_handle):

    serial_handle.flushInput()

    cnt =0

    while 1:

         din = serial_handle.read(30)

       

         cnt +=1

         #loop execution 8 times

         if len(din) ==0 and cnt < 8:

             continue

         if len(din) ==30 and din[0] ==53 and din[1] ==53 and din[26] ==70 and din[27] ==69 and din[28]==70 and din[29]==70:

             print(din)

             return din.decode('utf-8')

         elif cnt ==8 :

             print("Can not receive data from power board")

             return ""

         serial_handle.flushInput()

def convertGPS(gps):

        gps_la = gps[0:8]

        gps_lo = gps[8:16]

      

        list_la = []

        list_lo = []

        for i in range(4):

                list_la.append(int(gps_la[6-i*2:8-i*2],16))

        la = str(struct.unpack('<f', struct.pack('4B', *list_la))[0]).zfill(20)

        for i in range(4):

                list_lo.append(int(gps_lo[6-i*2:8-i*2],16))

        lo = str(struct.unpack('<f', struct.pack('4B', *list_lo))[0]).zfill(20)

       

        return la,lo

def convertGPSOrientation(gps):

        gps_n=''

        gps_e=''

        

        #NORTH,SOUTH,EAST,WEST,

        if gps[0:2]=='4E' and gps[2:4]=='45':

            

             gps_n ='N'

             gps_e ='E'

        if gps[0:2]=='53' and gps[2:4]=='45':

             gps_n ='S'

             gps_e ='E'

        if gps[0:2]=='4E' and gps[2:4]=='57':

             gps_n ='N'

             gps_e ='W'

        if gps[0:2]=='53' and gps[2:4]=='57':

             gps_n ='S'

             gps_e ='W'

        return  gps_n,gps_e

def gateIsOpened(gate_sign):

   

    if gate_sign=='0':

        flag=[0,0]

        print("front gate closed,back gate closed")

        return flag

    if gate_sign=='1':

        flag=[1,0]

        print("front gate opened,back gate closed")

        return flag

    if gate_sign=='2':

        flag=[0,1]

        print("front gate closed,back gate opened")

        return flag

    if gate_sign=='3':

        flag=[1,1]

        print("front gate opened,back gate opened")

        return flag

PB_data = serialRead(ser_intf)

print('---------------------pb_data-----------------------------------')

la,lo =convertGPS(PB_data[4:20])

print('-----------------gps--------------------------------')

print('la',la)

print('lo',lo)

gps_n,gps_e=convertGPSOrientation(PB_data[20:24])

print(gps_e)

print(gps_n)

flag=gateIsOpened(PB_data[3])

print('flag',flag)

根据串口协议，转换ASCII成utf-8格式。数值转换成十进制，比如5 十进制是53，从串口接收到的数值是53。门的信号为00是都关，01是前门开，以此类推，

gps是怎样解析的，从2到9个字节是gps信号。