I’m trying to communicate with IKA hardware EUROSTAR 60. I can read data with no problem. But when I try to output a value(adjusting), my code fails and there is no error message whatsoever. The hardware is connected to my computer using a USB cable.

import serial
import time

serial_port = 'COM7'
baud_rate = 9600

def send_command(ser, command):
    try:
        full_command = f'{command} rn'
        print(f"Sending command: '{full_command.strip()}'")
        ser.write(full_command.encode())
        time.sleep(0.5)
        response = ser.readline().decode().strip()
        print(f"Response: '{response}'")
        return response
    except Exception as e:
        print(f"Error sending command: {e}")
        return None

def main():
    try:
        ser = serial.Serial(serial_port, baudrate=baud_rate, bytesize=serial.SEVENBITS, parity=serial.PARITY_EVEN, stopbits=serial.STOPBITS_ONE, timeout=1)
        time.sleep(2)

        speed_limit = 213
        command = f'OUT_SP_4 {speed_limit}'
        response = send_command(ser, command)
        if response:
            print(f"Speed limit set to {speed_limit} RPM")
        else:
            print("Failed to set speed limit.")

    except Exception as e:
        print(f"Error: {e}")

    finally:
        ser.close()

if __name__ == "__main__":
    main()

The code above tries to change the ‘set rpm’ value on the device to 213. But the response I get is empty and the value on the device stays the same.

Does anyone know how to communicate correctly?