test_serial.py

import serial
import time
import sys

try:
    print("Opening serial connection to ESP32...")
    ser = serial.Serial('/dev/ttyACM0', 115200, timeout=0.1)
    print('Serial opened successfully')
    
    print("Testing ESP32 communication...")
    for i in range(20):
        # Try different commands
        commands = [b'\r\n', b'AT\r\n', b'help\r\n', b'\x03']  # Last one is Ctrl+C
        
        ser.write(commands[i % len(commands)])
        time.sleep(0.1)
        
        data = ser.read(1000)
        if data:
            print(f'Response {i}: {data.decode("utf-8", errors="ignore")}')
        else:
            print(f'No response {i}')
        
        time.sleep(0.2)
    
    ser.close()
    print("Serial test completed")
    
except serial.SerialException as e:
    print(f'Serial error: {e}')
    print("Device likely disconnected during test")
except Exception as e:
    print(f'Unexpected error: {e}')