ESP32: WiFi UDP Echo Hello

Sumber: http://www.iotsharing.com/2017/06/how-to-use-udpip-with-arduino-esp32.html

Server

import socket

# bind all IP
HOST = '0.0.0.0' 
# Listen on Port 
PORT = 44444 
#Size of receive buffer   
BUFFER_SIZE = 1024    
# Create a TCP/IP socket
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
# Bind the socket to the host and port
s.bind((HOST, PORT))
while True:
    # Receive BUFFER_SIZE bytes data
    # data is a list with 2 elements
    # first is data
    #second is client address
    data = s.recvfrom(BUFFER_SIZE)
    if data:
        #print received data
        print('Client to Server: ' , data)
        # Convert to upper case and send back to Client
        s.sendto(data[0].upper(), data[1])
# Close connection
s.close() 

ESP32

#include <WiFi.h>
#include <WiFiUdp.h>

/* WiFi network name and password */
const char * ssid = "HUAWEI-1A73";
const char * pwd = "52408495";

// IP address to send UDP data to.
// it can be ip address of the server or 
// a network broadcast address
// here is broadcast address
const char * udpAddress = "192.168.8.100";
const int udpPort = 44444;

//create UDP instance
WiFiUDP udp;

void setup(){
  Serial.begin(115200);
  
  //Connect to the WiFi network
   WiFi.begin(ssid, pwd);
  Serial.println(""); 

  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
  //This initializes udp and transfer buffer
  udp.begin(udpPort);
} 

void loop(){
  //data will be sent to server
  uint8_t buffer[50] = "hello world";
  //send hello world to server
  udp.beginPacket(udpAddress, udpPort);
  udp.write(buffer, 11);
  udp.endPacket();
  memset(buffer, 0, 50);
  //processing incoming packet, must be called before  reading the buffer
  udp.parsePacket();
  //receive response from server, it will be HELLO WORLD
  if(udp.read(buffer, 50) > 0){
    Serial.print("Server to client: ");
    Serial.println((char *)buffer);
  }
  //Wait for 1 second
  delay(1000);
}

Referensi

• http://www.iotsharing.com/2017/06/how-to-use-udpip-with-arduino-esp32.html

Pranala Menarik

• ESP32