Python serial Threading

[rev_ollie]

Hi again,

I've been looking more at reading serial - this time with a GUI in front. After attempts to get it working I thought it best to try threading to perform the task.
What it should do is read the serial port and update a label with the frame data. When you press the start button it works just fine the first time but then doesn't update it with further data.

I've therefor concluded I might need a further loop somewhere to call the thread again but I've not had any luck. Can someone take a look at the code below and possibly give me a starting point to allow it to continually update?

The threading code was an example I found which I have edited - and I'm very new at it so I've probably not done it correctly. I'm not sure I have actually called the function within the thread correctly...however if someone can see something I am missing that would be great.

Thanks,

import wx
import serial
import datetime;
import time
import wx
from threading import Thread
from wx.lib.pubsub import Publisher


class TestThread(Thread):

    def __init__(self):
        Thread.__init__(self)
        self.start()
        self.XBEE()


    def XBEE(self):
        self.ser = serial.Serial('com7',9600,timeout=1)
        while True:
            try:
                Data_in = self.ser.readline().encode('hex')
                for data in Data_in.split('7e'):
                    if data[6:8] == '90':
                        print "=========================="
                        print "Found Packet: 7e%s" % data
                        print "Packet Type = ZgBee RX Packet"
                        self.AH = data [10:18]
                        self.AL = data [18:26]
                        print "Device Address = ", self.AH, self.AL
                        self.TH = data [34:36]
                        self.TL = data [38:40]
                        self.THc = int(self.TH, 16)
                        self.TLc = int(self.TL, 16)

                        if data[41:42] == '0':
                            self.Temp = "%d.%d" % (self.THc, self.TLc)
                            print "Temperature:", self.Temp
                        else:
                            self.Temp = "-%d.%d" % (self.THc, self.TLc)
                            print "Temperature:", self.Temp

                        now = datetime.datetime.now()
                        self.CUR_YEAR = now.year
                        self.CUR_MONTH = now.month
                        self.CUR_DAY = now.day
                        self.CUR_HOUR = now.hour
                        self.CUR_MIN = now.minute
                        self.CUR_SEC = now.second
                        self.CUR_MSEC = now.microsecond
                        self.timedate = "Time and Date: %d/%d/%d - %d:%d:%d:%d" % (self.CUR_DAY, self.CUR_MONTH, self.CUR_YEAR, self.CUR_HOUR, self.CUR_MIN, self.CUR_SEC, self.CUR_MSEC)
                        print self.timedate
                        print "======================="
                        print " "   
                        Publisher().sendMessage("update", self.Temp)

            except ValueError:
                print "Invalid Number detected" 

########################################################################
class MyForm(wx.Frame):

    #----------------------------------------------------------------------
    def __init__(self):
        wx.Frame.__init__(self, None, wx.ID_ANY, "Tutorial")

        # Add a panel so it looks the correct on all platforms
        panel = wx.Panel(self, wx.ID_ANY)
        self.displayLbl = wx.StaticText(panel, label="Temperature Reading")
        self.btn = btn = wx.Button(panel, label="Start Reading")

        btn.Bind(wx.EVT_BUTTON, self.onButton)

        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(self.displayLbl, 0, wx.ALL|wx.CENTER, 5)
        sizer.Add(btn, 0, wx.ALL|wx.CENTER, 5)
        panel.SetSizer(sizer)
        Publisher().subscribe(self.updateDisplay, "update")

    #----------------------------------------------------------------------
    def onButton(self, event):
        TestThread()
        btn = event.GetEventObject()
        btn.Disable()

#----------------------------------------------------------------------
    def updateDisplay(self, msg):
        """
        Receives data from thread and updates the display
        """
        t = msg.data
        if isinstance(t, int):
            self.displayLbl.SetLabel(t)
        else:
            self.displayLbl.SetLabel("%s" % t)

# Run the program
if __name__ == "__main__":
    app = wx.PySimpleApp()
    frame = MyForm().Show()
    app.MainLoop()