nmea-parser 0.2.0

Python library to parse NMEA streams

NMEA Parser

A library used to decode NMEA data streams from GNSS receivers. Capable of parsing a text file containing NMEA data or reading from a serial port real time.

This library is currently in Beta and is subject to change any time.

Dependencies

PySerial is the only dependency. See requirements.txt.

Usage

See www.bek.sh/nmea-parser for a full manual.

Examples

Opening and Reading a Serial Port

It is highly sugested that you use all input streams within a context manager (with statement) as shown below.

from nmea import input_stream

stream = input_stream.GenericInputStream.open_stream('/dev/ttyACM0', 9600)

print(stream)

with stream:
    print(stream.get_line())

If you must use an input stream without a context manager, make sure that the ensure_closed() function is called prior to exit:

from nmea import input_stream

stream = input_stream.GenericInputStream.open_stream('/dev/ttyACM0', 9600)

print(stream)
print(stream.get_line())
stream.ensure_closed()      # You must not forget to manually close the stream.

Using a context manager ensures that the port is always closed should your program halt unexpectedly.

Getting Position Data and Logging to a Database

The DataFrame object contains properties that allow you to access your current position and movement information. The logging module allows you to record these objects in a database. The logging module has built-in SQLite support.

from nmea import input_stream, data_frame, logging

stream = input_stream.GenericInputStream.open_stream('/dev/ttyACM0', 9600)

db = logging.SQLiteConnection.from_path('./example.sqlite')

print(stream)

with stream:
    new_frame = data_frame.DataFrame.get_next_frame(stream)

    print("Current GPS time:", new_frame.gps_time)
    print("Current Latitude:", new_frame.latitude)
    print("Current Longitude:", new_frame.longitude)
    print("Current Speed:", new_frame.velocity)
    print("Current heading:", new_frame.track)
    print("Number of Satellites above:", new_frame.nsats)

    db.insert_dataframe(new_frame)

Changelog

• 0.2.0 (2021-06-01)

  • Add ability to record a raw text dump of an incoming NMEA stream
  • Majorly simplify the built in logging module
  • Completely depreciate the nmea parser module.
  • Fix a bug where NMEA sentences without a fix threw an index error
  • Clean source code

• 0.1.2 (2021-05-25)

  • Fix 'inaproprate ioctl for device' error from serial library

• 0.1.1 (2021-05-24)

  • Improve safety of file handling in input stream module
  • Bug fixes in type checking
  • Fix absolute imports in project
  • Small fixes to documentation

• 0.1.0 (2021-05-20):

  • Inital release