Python Pyserial - 线程

Question

Python 2.7

这是我的代码。你能告诉我什么是错的。这是我连续两天研究穿线后想出来的野兽。

当我不使用线程时，串行通信工作。

main()

Answer 1

您没有正确同步线程。我建议将ser对象放入全局命名空间并使用锁，互斥锁或信号量来防止两个线程同时访问单个ser对象。

本周的Python模块最好地解释了here

Answer 2

使用锁的示例

import threading
import time
import sys
import serial
import os
import time

def Task1(lck,ser):

    while 1:

        print "Inside Thread 1"
        lck.acquire()
        ser.write('\x5A\x03\x02\x02\x02\x09') # Byte ArrayTo Control a MicroProcessing Unit
        b = ser.read(7)
        lck.release()
        print b.encode('hex')
        print "Thread 1 still going on"
        time.sleep(1)


def Task2(lck,ser):

    print "Inside Thread 2"
    print "I stopped Task 1 to start and execute Thread 2"
    lck.acquire()
    ser.write('x5A\x03\x02\x08\x02\x0F')
    c = ser.read(7)
    lck.release()
    print c.encode('hex')
    print "Thread 2 complete"


def Main():
    ser = serial.Serial(3, 11520)
    lck = threading.Lock()
    t1 = threading.Thread(target = Task1, args=[ser,lck])
    t2 = threading.Thread(target = Task2, args=[ser,lck])
    print "Starting Thread 1"
    t1.start()
    print "Starting Thread 2"
    t2.start()

    print "=== exiting ==="

    ser.close()

if __name__ == '__main__':

    Main()