How to read Serial data with Python from more then one Arduino ADC?

Question

I am begginer in Python. I am trying to write serial port data from Arduino to CSV file in Python. I want to save data in format: time, sensor1, sensor2 as numbers allowing to open them in Excel in separate columns. My code allows to obtain CSV as follows:

12:25:57,"294,293" I cannot remove the quotations.

My Arduino code for serial output:

Serial.print(sensorValue_1);
Serial.print(",");
Serial.println(sensorValue_2);
delay(1000);

My Python code:

import csv
import serial
import time

ser=serial.Serial("COM15", 9600)
ser.flushInput()

while True:
    ser_bytes = ser.readline().decode().strip()


    t = time.localtime()
    decoded_time = time.strftime('%H:%M:%S', t)
    print(decoded_time, ser_bytes)
    with open("test_file.csv", "a", newline='') as f:
        writer = csv.writer(f, delimiter = ",")
        writer.writerow([decoded_time, ser_bytes])
        f.close()

I will appreciate the help.

Answer 1

I edited your code and add some comments. try this if this is what you need.

import csv
import serial
import time

ser=serial.Serial("COM15", 9600)
ser.flushInput()

while True:
    #use split(',') to seperate ser_byte string to list
    ser_bytes = ser.readline().decode().strip().split(',')

    # using list comprehension to perform conversion to int
    new_ser_bytes = [int(i) for i in ser_bytes]

    #new_ser_bytes[0] is sensorValue_1
    #new_ser_bytes[1] is sensorValue_2
    
    t = time.localtime()
    decoded_time = time.strftime('%H:%M:%S', t)
    #print(decoded_time, ser_bytes)
    with open("test_file.csv", "a", newline='') as f:
        writer = csv.writer(f, delimiter = ",")
        #writerow with seperate sensorValue
        writer.writerow([decoded_time, new_ser_bytes[0], new_ser_bytes[1]])
        f.close()