1  # Simple GPS module demonstration.
 2  # Will wait for a fix and print a message every second with the current location
 3  # and other details.
 4  import time
 5  import board
 6  import busio
 7  
 8  import adafruit_gps
 9  
10  # Create a serial connection for the GPS connection using default speed and
11  # a slightly higher timeout (GPS modules typically update once a second).
12  # These are the defaults you should use for the GPS FeatherWing.
13  # For other boards set RX = GPS module TX, and TX = GPS module RX pins.
14  uart = busio.UART(board.TX, board.RX, baudrate=9600, timeout=10)
15  
16  # for a computer, use the pyserial library for uart access
17  # import serial
18  # uart = serial.Serial("/dev/ttyUSB0", baudrate=9600, timeout=10)
19  
20  # If using I2C, we'll create an I2C interface to talk to using default pins
21  # i2c = board.I2C()
22  
23  # Create a GPS module instance.
24  gps = adafruit_gps.GPS(uart, debug=False)  # Use UART/pyserial
25  # gps = adafruit_gps.GPS_GtopI2C(i2c, debug=False)  # Use I2C interface
26  
27  # Initialize the GPS module by changing what data it sends and at what rate.
28  # These are NMEA extensions for PMTK_314_SET_NMEA_OUTPUT and
29  # PMTK_220_SET_NMEA_UPDATERATE but you can send anything from here to adjust
30  # the GPS module behavior:
31  #   https://cdn-shop.adafruit.com/datasheets/PMTK_A11.pdf
32  
33  # Turn on the basic GGA and RMC info (what you typically want)
34  gps.send_command(b"PMTK314,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0")
35  # Turn on just minimum info (RMC only, location):
36  # gps.send_command(b'PMTK314,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0')
37  # Turn off everything:
38  # gps.send_command(b'PMTK314,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0')
39  # Tuen on everything (not all of it is parsed!)
40  # gps.send_command(b'PMTK314,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0')
41  
42  # Set update rate to once a second (1hz) which is what you typically want.
43  gps.send_command(b"PMTK220,1000")
44  # Or decrease to once every two seconds by doubling the millisecond value.
45  # Be sure to also increase your UART timeout above!
46  # gps.send_command(b'PMTK220,2000')
47  # You can also speed up the rate, but don't go too fast or else you can lose
48  # data during parsing.  This would be twice a second (2hz, 500ms delay):
49  # gps.send_command(b'PMTK220,500')
50  
51  # Main loop runs forever printing the location, etc. every second.
52  last_print = time.monotonic()
53  while True:
54      # Make sure to call gps.update() every loop iteration and at least twice
55      # as fast as data comes from the GPS unit (usually every second).
56      # This returns a bool that's true if it parsed new data (you can ignore it
57      # though if you don't care and instead look at the has_fix property).
58      gps.update()
59      # Every second print out current location details if there's a fix.
60      current = time.monotonic()
61      if current - last_print >= 1.0:
62          last_print = current
63          if not gps.has_fix:
64              # Try again if we don't have a fix yet.
65              print("Waiting for fix...")
66              continue
67          # We have a fix! (gps.has_fix is true)
68          # Print out details about the fix like location, date, etc.
69          print("=" * 40)  # Print a separator line.
70          print(
71              "Fix timestamp: {}/{}/{} {:02}:{:02}:{:02}".format(
72                  gps.timestamp_utc.tm_mon,  # Grab parts of the time from the
73                  gps.timestamp_utc.tm_mday,  # struct_time object that holds
74                  gps.timestamp_utc.tm_year,  # the fix time.  Note you might
75                  gps.timestamp_utc.tm_hour,  # not get all data like year, day,
76                  gps.timestamp_utc.tm_min,  # month!
77                  gps.timestamp_utc.tm_sec,
78              )
79          )
80          print("Latitude: {0:.6f} degrees".format(gps.latitude))
81          print("Longitude: {0:.6f} degrees".format(gps.longitude))
82          print("Fix quality: {}".format(gps.fix_quality))
83          # Some attributes beyond latitude, longitude and timestamp are optional
84          # and might not be present.  Check if they're None before trying to use!
85          if gps.satellites is not None:
86              print("# satellites: {}".format(gps.satellites))
87          if gps.altitude_m is not None:
88              print("Altitude: {} meters".format(gps.altitude_m))
89          if gps.speed_knots is not None:
90              print("Speed: {} knots".format(gps.speed_knots))
91          if gps.track_angle_deg is not None:
92              print("Track angle: {} degrees".format(gps.track_angle_deg))
93          if gps.horizontal_dilution is not None:
94              print("Horizontal dilution: {}".format(gps.horizontal_dilution))
95          if gps.height_geoid is not None:
96              print("Height geo ID: {} meters".format(gps.height_geoid))