デジタルマルチメータADVANTEST R6452Aの値をRS-232Cで取得して保存してみる

# please setting talkonly mode with header

import serial
import datetime
import time
import sys

args = sys.argv
noheader = False
if len(args) == 1:
    print("Select Port", file=sys.stderr)
    print("ex. python3 R644x5xTALKONLY.py /dev/ttyUSB0", file=sys.stderr)
    exit()
if len(args) == 3:
    if args[2] == 'noheader':
        noheader = True

port = args[1]
baud_rate = 9600

def extract_value(response):
    return response[3:]

def extract_header(response):
    return response[:3]

def split_data(response):
    return [item.strip() for item in response.split(',')]

# init
try:
    ser = serial.Serial(port, baud_rate, timeout=1)
except serial.SerialException:
    print("fail to open Serial port", file=sys.stderr)
    exit()

# print data
try:
    header = ''
    double = False

    while ser.in_waiting < 1:
        time.sleep(0.01)

    data = ser.readline().decode().strip()
    double = False
    spdata = split_data(data)
    if len(spdata) == 1:
        header = extract_header(spdata[0])
        if noheader == False:
            print(f"day,hour,minute,second,msec,{header}")
    elif len(spdata) == 2:
        header = [extract_header(spdata[0]), extract_header(spdata[1])]
        double = True
        if noheader == False:
            print(f"day,hour,minute,second,msec,{header[0]},{header[1]}")
    else:
        print(data, file=sys.stderr)
        print("invalid header", file=sys.stderr)

    while True:
        if ser.in_waiting > 0:
            data = ser.readline().decode().strip()  # read serial
            timestamp = datetime.datetime.now().strftime('%d,%H,%M,%S,%f')[:-3]  # timestamp
            spdata = split_data(data)
            if double:
                if header != [extract_header(spdata[0]), extract_header(spdata[1])]:
                    print("header was changed", file=sys.stderr)
                    break
                print(f"{timestamp},{extract_value(spdata[0])},{extract_value(spdata[1])}")
            else:
                if header != extract_header(spdata[0]):
                    print("header was changed", file=sys.stderr)
                    break
                print(f"{timestamp},{extract_value(spdata[0])}")
except KeyboardInterrupt:
    print()
finally:
    ser.close()