python repeat timer with gps

[승환]

Hello, I'm trying to make timer which spit out gps signal every 10 or 60 seconds.

here is my code.

*

**import threading
import time
import serial
import datetime, string
from pynmea import nmea
def init_serial():
    COMNUM = 13  
    global ser  
    ser = serial.Serial()
    ser.baudrate = 9600
    ser.port = 12 
    ser.timeout = 1 
    ser.open() **

def to_degrees(lats, longs): #convert nmea signal to usual altitude, longitude
    lat_deg = lats[0:2]
    lat_mins = lats[2:4]
    lat_secs = round(float(lats[5:])*60/10000, 2)
    lat_str = lat_deg + u'°'+ lat_mins + string.printable[68] + str(lat_secs) + string.printable[63]

    lon_deg = longs[0:3]
    lon_mins = longs[3:5]
    lon_secs = round(float(longs[6:])*60/10000, 2)
    lon_str = lon_deg + u'°'+ lon_mins + string.printable[68] + str(lon_secs) + string.printable[63]
    return [lat_str, lon_str]

def gpgga():  # get gps signal
    data = ser.readline()
    if data[0:6] == "$GPGGA":
        gpgga = nmea.GPGGA()
        gpgga.parse(data)
        lats = gpgga.latitude
        lat_dir = gpgga.lat_direction
        longs = gpgga.longitude
        long_dir = gpgga.lon_direction
        alt = gpgga.antenna_altitude
        time = gpgga.timestamp
        lat_lon = to_degrees(lats, longs)  
        print time   
        print "Latitude: ", lat_lon[0]+lat_dir ,"&", "Longitude: ", lat_lon[1]+long_dir
        print "Altitude: ", alt

class Timer(threading.Thread):  # Repeat timer and here is questions.
    def __init__(self):
        threading.Thread.__init__(self)
        self.event = threading.Event()

    def run(self):
        while not self.event.is_set():
            init_serial()
            print datetime.datetime.now()
            gpgga()
            self.event.wait(14.2857142857142857142857)
            ser.close()

    def stop(self):
        self.event.set()
i=0
while i<100:
    tmr=Timer()
    tmr.start()
    print i
    i=i+1
    tmr.stop()
    time.sleep(10)

ser.close()* 

at the timer part, self.event.wait(14.2857142857142857142857) is waiting function but it didn't work and only time.sleep(10) function works.

what's wrong? and how to fix it

[Gribouillis]

I've always found the threading module easier when Condition instances are used. Here is a periodic timer implemented with a condition:

from __future__ import print_function 
import datetime as dt
import threading as th
import time

class PeriodicTimer(th.Thread):
    def __init__(self, delay):
        th.Thread.__init__(self)
        self.locked = th.Condition()
        self.delay = float(delay)
        assert self.delay > 0.0
        self.stopped = False

    def run(self):
        print("Periodic timer starting")
        self.stopped = False
        with self.locked:
            while not self.stopped:
                print("Periodic timer:", dt.datetime.now())
                self.locked.wait(self.delay)
        print("Periodic timer exiting")

    def stop(self):
        with self.locked:
            self.stopped = True
            self.locked.notify()
        self.join()

if __name__ == '__main__':
    t = PeriodicTimer(0.37)
    t.start()
    time.sleep(3)
    t.stop()

""" my output -->
Periodic timer starting
Periodic timer: 2015-06-03 09:52:42.774104
Periodic timer: 2015-06-03 09:52:43.153796
Periodic timer: 2015-06-03 09:52:43.523985
Periodic timer: 2015-06-03 09:52:43.894159
Periodic timer: 2015-06-03 09:52:44.264333
Periodic timer: 2015-06-03 09:52:44.634513
Periodic timer: 2015-06-03 09:52:45.004683
Periodic timer: 2015-06-03 09:52:45.374836
Periodic timer: 2015-06-03 09:52:45.745005
Periodic timer exiting
"""