Notes

#include <ESP8266WiFi.h>
#include <WiFiUdp.h>

const char* ssid = "orion";
const char* password = "16161606";
const char* ip = "192.168.1.151";

WiFiUDP Udp;
unsigned int localUdpPort = 4211; // local port to listen on
char incomingPacket[255]; // buffer for incoming packets
char replyPacekt[] = "Hi there! Got the message :-)"; // a reply string to send back


void setup()
{
Serial.begin(115200);
Serial.println();

Serial.printf("Connecting to %s ", ssid);
WiFi.begin(ssid, password);
WiFi.config(IPAddress(192, 168, 1, 152), IPAddress(192, 168, 1, 1), IPAddress(255, 255, 255, 0));
while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(".");
}
Serial.println(" connected");

Udp.begin(localUdpPort);
Serial.printf("Now listening at IP %s, UDP port %dn", WiFi.localIP().toString().c_str(), localUdpPort);
}

void gonder(){
Udp.beginPacket(ip, 4210);
Udp.print("123456789");
Serial.println("gonder");
Udp.endPacket();
}

void loop()
{
// gonder();
//delay(1000);
int packetSize = Udp.parsePacket();
if (packetSize)
{
// receive incoming UDP packets
//Serial.printf("Received %d bytes from %s, port %dn", packetSize, ip, Udp.remotePort());
int len = Udp.read(incomingPacket, 255);
if (len > 0)
{
incomingPacket[len] = 0;
}
Serial.printf("%sn", incomingPacket);

// send back a reply, to the IP address and port we got the packet from
// Udp.beginPacket(Udp.remoteIP(), Udp.remotePort());
// Udp.write(replyPacekt);
// Udp.endPacket();
}
}