An ESP32 script that connects to WIFI and starts a UDP server

main.py

import network
import utime
import socket
import machine

p2 = machine.Pin(2, machine.Pin.OUT) # create input pin on GPIO2 (builtin LED)
p2.off()

def toggle_pin():
    p2.value(1) if p2.value() == 0 else p2.value(0)

tim0 = machine.Timer(0)

ssid = "my_ssid"
passwd = "my_password"

sta_if = network.WLAN(network.STA_IF) # create station interface

def connect():
    count = 0
    if sta_if.isconnected():
        sta_if.disconnect()
        print ('started in the connected state')
        print ('but now it is disconnected')
    else:
        print ('started in the disconnected state')

    utime.sleep(1) #  maybe try reducing this

    if not sta_if.isconnected():
        print('connecting to hotspot...')
        sta_if.ifconfig(('192.168.0.112', '255.255.255.0', '192.168.0.1', '8.8.8.8'))
        sta_if.active(True)

        try:
            sta_if.connect(ssid, passwd)
        except OSError as error:
            try:
                with open('errors.txt', 'a') as outfile:
                    outfile.write(str(error) + '\n')
            except OSError:
                pass

        while (count < 5):
            count += 1

            if (sta_if.isconnected()):
                count = 0
                print ('network config:', sta_if.ifconfig())
                tim0.init(period=2000, mode=machine.Timer.PERIODIC, callback=lambda t:toggle_pin())
                break

            print ('.', end = '')
            utime.sleep(1)

    if (count == 5):
        try:
            with open('errors.txt', 'a') as outfile:
                outfile.write('failed to connect after 5 tries' + '\n')
        except OSError:
            pass

        disconnect() # or you could get errors

        machine.reset() #  start again
        
    try:
        rssi = sta_if.status('rssi')
        print ('RSSI = ' + str(rssi) + 'dBm')
    except:
        print ('signal level too low')

    count = 0 #  reset count

    utime.sleep(1)

def disconnect():
    try:
        # disconnects STA, even if it is not connected
        sta_if.disconnect()
    except:
        pass

    sta_if.active(False)

    utime.sleep(1)

connect()

local_ip = '0.0.0.0'
server = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) # UDP protocol
server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server.bind((local_ip, 61234))
print("start Listening at 61234. Use nc -u 192.168.0.112 61234 and start sending messages")

while True:
    data, client_addr = server.recvfrom(1000)
    print('client connected from', client_addr)
    print("data: ", data)