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GNU nano 2.2.6                                File: grove_gps_rpi_mod.py

#!/usr/bin/env python # # GrovePi Example for using the Grove GPS Module http://www.seeedstudio.com/depot/Grove-GPS-p-959.html?cPath=25_130 # # The GrovePi connects the Raspberry Pi and Grove sensors. You can learn more about GrovePi here: http://www.dexterindustries.com/GrovePi # # Have a question about this example? Ask on the forums here: http://www.dexterindustries.com/forum/?forum=grovepi # # LICENSE: # These files have been made available online through a [Creative Commons Attribution-ShareAlike 3.0](http://creativecommons.org/licenses/by-sa$ # # History # ------------------------------------------------ # Author Date Comments # Karan 21 Aug 14 Initial Authoring

import serial, time import smbus import math import RPi.GPIO as GPIO import struct import sys

ser = serial.Serial('/dev/ttyAMA0', 9600, timeout = 0) #Open the serial port at 9600 baud ser.flush()

class GPS: #The GPS module used is a Grove GPS module http://www.seeedstudio.com/depot/Grove-GPS-p-959.html inp=[] # Refer to SIM28 NMEA spec file http://www.seeedstudio.com/wiki/images/a/a0/SIM28_DATA_File.zip GGA=[]

#Read data from the GPS
def read(self):
        while True:
                GPS.inp=ser.readline()
                if GPS.inp[:6] =='$GPGGA': # GGA data , packet 1, has all the data we need
                        break
                time.sleep(0.1)     #without the cmd program will crach
        try:
                ind=GPS.inp.index('$GPGGA',5,len(GPS.inp))      #Sometimes multiple GPS data packets come into the stream. Take the dat$
                GPS.inp=GPS.inp[ind:]
        except ValueError:
                print ""
        GPS.GGA=GPS.inp.split(",")      #Split the stream into individual parts
        return [GPS.GGA]

#Split the data into individual elements
def vals(self):
        time=GPS.GGA[1]
        lat=GPS.GGA[2]
        lat_ns=GPS.GGA[3]
        long=GPS.GGA[4]
        long_ew=GPS.GGA[5]
        fix=GPS.GGA[6]
        sats=GPS.GGA[7]
        alt=GPS.GGA[9]
        return [time,fix,sats,alt,lat,lat_ns,long,long_ew]

# Convert to decimal degrees
def decimal_degrees(self, raw_degrees):
        degrees = float(raw_degrees) // 100
        d = float(raw_degrees) % 100 / 60
        return degrees + d

g=GPS() f=open("gps_data.csv",'w') #Open file to log the data f.write("name,latitude,longitude\n") #Write the header to the top of the file ind=0 while True: try: x=g.read() #Read from GPS [t,fix,sats,alt,lat,lat_ns,long,long_ew]=g.vals() #Get the individial values

# Convert to decimal degrees
lat = g.decimal_degrees(float(lat))
if lat_ns == "S":
        lat = -lat

long = g.decimal_degrees(float(long))
if long_ew == "W":
        long = -long

print "Time:",t,"Fix status:",fix,"Sats in view:",sats,"Altitude",alt,"Lat:",lat,lat_ns,"Long:",long,long_ew

print "Time:",str(t),"Fix status:",str(fix),"Sats in view:",str(sats),"Altitude",str(alt),"Lat:",str(float(lat)//100+(float(lat$

s=str(t)","+str(float(lat)//100(float(lat)%100)/60*1)","+str(float(long)//100(float(long)%100)/60)+"\n"

s=str(t)+";"+str(fix)+";"+str(sats)+";"+str(alt)+";"+str(float(lat))+";"+lat_ns+";"+str(float(long))+";"+long_ew+"\n"

        f.write(s)      #Save to file
        time.sleep(2)
except IndexError:
        print "Unable to read"
except KeyboardInterrupt:
        f.close()
        print "Exiting"
        sys.exit(0)