read_wxt530.py

import serial
import time
import argparse
import csv

from datetime import datetime

# To display current ports:
# python -m serial.tools.list_ports

## needs a search ports functionality
    
def pollsave(ser, args):
    # check if you need to poll the data
    if args.poll is True:
        # Initalize communication with the instrument
        ser.write(bytearray(args.query + '\r\n', 'utf-8'))
    # Read the incoming serial data
    data = ser.readline()
    # if verbose is set, print output
    if args.verbose:
        print(data)
    # check to make sure data are being returned
    if data:
        # define a timestamp for the data and append to data string
        time = datetime.now().strftime("%Y%m%dT%H:%M:%S.%f")
        datatime = time + ','+ data.decode('utf-8')
    else:
        datatime = None

    return datatime

def main(args):
    # start serial connection:
    with serial.Serial(args.device, args.baud_rate, timeout = 1) as ser:
        # create a file to write data to
        nfile = 'WXT536_' + args.site + '_' + datetime.now().strftime("%Y%m%d.%H%M%S")
        # check desired output from user. supports netcdf or csv
        if args.output == 'nc' or args.output == 'netcdf':
            filename = nfile + '.nc'
        else:
            filename = nfile + '.csv'
        # While Serial connection is valid
        while True:
            # query the instrument
            ndata = pollsave(ser, args)
            # check to see if anything is returned
            ### Add debug line here? -> check how to store values
            if ndata:
                if args.output == 'nc' or args.output == 'netcdf':
                    print("Needs support... switch to csv")
                else:
                    # Append to the file. 
                    with open(filename, "a") as myfile:
                        try:
                            writer = csv.writer(myfile, delimiter=",")
                            writer.writerow(ndata.strip().split(','))
                        except:
                            print('Unable to write to file: ', filename)
            time.sleep(args.freq)
 
if __name__ == '__main__':
     parser = argparse.ArgumentParser(
            description="Script for interfacing with Viasala WXT 2D anemometer data")
 
     parser.add_argument("--verbose",
                         action="store_true",
                         dest='verbose',
                         help="Enable Output of Serial Communication to Screen"
                         )
     parser.add_argument("--device",
                         type=str,
                         dest='device',
                         default="/dev/ttyUSB0",
                         help="Specific Serial Port for Device Communication"
                         )
     parser.add_argument("--baudrate",
                         type=int,
                         dest='baud_rate',
                         default=19200,
                         help="Baud Rate for Serial Device Communication"
                         )
     parser.add_argument("--poll",
                         type=bool,
                         default=False,
                         help="Boolean Flag for if data are polled"
                         )
     parser.add_argument("--query",
                         type=str,
                         default="0R",
                         help="ASCII query command to send to the instrument"
                        )
     parser.add_argument("--format",
                         type=str,
                         dest='output',
                         default="csv",
                         help="output file format (csv or nc)"
                         )
     parser.add_argument("--site",
                         type=str,
                         dest="site",
                         default="atmos",
                         help="Site Identifier for Filename"
                         )
     parser.add_argument("--frequency",
                         type=int,
                         default=1,
                         dest="freq",
                         help="Temporal frequency of the data aquesition"
                         )
     args = parser.parse_args()

     main(args)