1. from machine import Pin, UART, I2C
2. from ssd1306 import SSD1306_I2C
3.  
4. #Import utime library to implement delay
5. import utime, time
6.  
7. #Oled I2C connection
8. i2c=I2C(0,sda=Pin(0), scl=Pin(1), freq=400000)
9. oled = SSD1306_I2C(128, 64, i2c)
10.  
11. #GPS Module UART Connection
12. gps_module = UART(0, baudrate=9600, tx=Pin(12), rx=Pin(13))
13.  
14. #print gps module connection details
15. print(gps_module)
16.  
17. #Used to Store NMEA Sentences
18. buff = bytearray(255)
19.  
20. TIMEOUT = False
21.  
22. #store the status of satellite is fixed or not
23. FIX_STATUS = False
24. #Store GPS Coordinates
25. latitude = ""
26. longitude = ""
27. satellites = ""
28. gpsTime = ""
29.  
30.  
31. #function to get gps Coordinates
32. def getPositionData(gps_module):
33.     global FIX_STATUS, TIMEOUT, latitude, longitude, satellites, gpsTime
34.    
35.     #run while loop to get gps data
36.     #or terminate while loop after 5 seconds timeout
37.     timeout = time.time() + 30   # 8 seconds from now
38.     while True:
39.         gps_module.readline()
40.         buff = str(gps_module.readline())
41.         #parse $GPGGA term
42.         #b'$GPGGA,094840.000,2941.8543,N,07232.5745,E,1,09,0.9,102.1,M,0.0,M,,*6C\r\n'
43.         #print(buff)
44.         parts = buff.split(',')
45.        
46.         #if no gps displayed remove "and len(parts) == 15" from below if condition
47.         if (parts[0] == "b'$GNGGA" and len(parts) == 15):
48.             if(parts[1] and parts[2] and parts[3] and parts[4] and parts[5] and parts[6] and parts[7]):
49.                 print(buff)
50.                 print("Message ID  : " + parts[0])
51.                 print("UTC time    : " + parts[1])
52.                 print("Latitude    : " + parts[2])
53.                 print("N/S         : " + parts[3])
54.                 print("Longitude   : " + parts[4])
55.                 print("E/W         : " + parts[5])
56.                 print("Position Fix: " + parts[6])
57.                 print("n sat       : " + parts[7])
58.                
59.                 latitude = convertToDigree(parts[2])
60.                 # parts[3] contain 'N' or 'S'
61.                 if (parts[3] == 'S'):
62.                     latitude = -latitude
63.                 longitude = convertToDigree(parts[4])
64.                 # parts[5] contain 'E' or 'W'
65.                 if (parts[5] == 'W'):
66.                     longitude = -longitude
67.                 satellites = parts[7]
68.                 gpsTime = parts[1][0:2] + ":" + parts[1][2:4] + ":" + parts[1][4:6]
69.                 FIX_STATUS = True
70.                 break
71.                
72.         if (time.time() > timeout):
73.             TIMEOUT = True
74.             break
75.         utime.sleep_ms(500)
76.        
77. #function to convert raw Latitude and Longitude
78. #to actual Latitude and Longitude
79. def convertToDigree(RawDegrees):
80.  
81.     RawAsFloat = float(RawDegrees)
82.     firstdigits = int(RawAsFloat/100) #degrees
83.     nexttwodigits = RawAsFloat - float(firstdigits*100) #minutes
84.    
85.     Converted = float(firstdigits + nexttwodigits/60.0)
86.     Converted = '{0:.6f}'.format(Converted) # to 6 decimal places
87.     return str(Converted)
88.    
89.    
90. while True:
91.    
92.     getPositionData(gps_module)
93.  
94.     #if gps data is found then print it on lcd
95.     if(FIX_STATUS == True):
96.         print("fix......")
97.         oled.fill(0)
98.         oled.text("Lat: "+latitude, 0, 0)
99.         oled.text("Lng: "+longitude, 0, 10)
100.         oled.text("No of Sat: "+satellites, 0, 20)
101.         oled.text("Time: "+gpsTime, 0, 30)
102.         oled.show()
103.         print(latitude)
104.         print(longitude)
105.         print(satellites)
106.         print(gpsTime)
107.        
108.         FIX_STATUS = False
109.        
110.     if(TIMEOUT == True):
111.         print("Request Timeout: No GPS data is found.")
112.         #--------------------------------------------------
113.         #updated on 5-May-2022
114.         oled.fill(0)
115.         oled.text("No GPS data is found", 0, 0)
116.         oled.show()
117.         #--------------------------------------------------
118.         TIMEOUT = False
119.        
120.