[ESP8266-SSM EVM] ESP8266 웹서버 테스트
ESP8266의 가장 강점은 저렴한 가격의 WiFi 를 구현 할 수 있는것이 아닐까...
우선 가장 간단하게 테스트 해 볼 수 있는 웹서버 예제를 돌려 보자
Arrduino설치시 기본으로 제공하는 웹서버 예제를 다운로드 해서 테스트 해 보았다.
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <ESP8266mDNS.h>
const char* ssid = "****";
const char* password = "*****";
ESP8266WebServer server(80);
const int led = 13;
void handleRoot() {
digitalWrite(led, 1);
server.send(200, "text/plain", "hello from esp8266!");
digitalWrite(led, 0);
}
void handleNotFound(){
digitalWrite(led, 1);
String message = "File Not Found\n\n";
message += "URI: ";
message += server.uri();
message += "\nMethod: ";
message += (server.method() == HTTP_GET)?"GET":"POST";
message += "\nArguments: ";
message += server.args();
message += "\n";
for (uint8_t i=0; i<server.args(); i++){
message += " " + server.argName(i) + ": " + server.arg(i) + "\n";
}
server.send(404, "text/plain", message);
digitalWrite(led, 0);
}
void setup(void){
pinMode(led, OUTPUT);
digitalWrite(led, 0);
Serial.begin(115200);
WiFi.mode(WIFI_STA);
WiFi.begin(ssid, password);
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());
if (MDNS.begin("esp8266")) {
Serial.println("MDNS responder started");
}
server.on("/", handleRoot);
server.on("/inline", [](){
server.send(200, "text/plain", "this works as well");
});
server.onNotFound(handleNotFound);
server.begin();
Serial.println("HTTP server started");
}
void loop(void){
server.handleClient();
}
실행하면 접속 정보가 나온다.
Connected to KT_GiGA_DC3E
IP address: 172.30.1.19
MDNS responder started
HTTP server started
그 정보를 이용해서 해당 IP로 접속하면 간단한 웹페이지가 표시되는것을 확인 할 수 있다.
기본 코드는 확인되었으니 이제 좀더 복잡한 웹서버 예제를 돌려 보자
// Load Wi-Fi library
#include <ESP8266WiFi.h>
// Replace with your network credentials
const char* ssid = "****";
const char* password = "****";
// Set web server port number to 80
WiFiServer server(80);
// Variable to store the HTTP request
String header;
// Auxiliar variables to store the current output state
String output5State = "off";
String output4State = "off";
// Assign output variables to GPIO pins
const int output5 = 5;
const int output4 = 16;
void setup() {
Serial.begin(115200);
// Initialize the output variables as outputs
pinMode(output5, OUTPUT);
pinMode(output4, OUTPUT);
// Set outputs to LOW
digitalWrite(output5, LOW);
digitalWrite(output4, LOW);
// Connect to Wi-Fi network with SSID and password
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
// Print local IP address and start web server
Serial.println("");
Serial.println("WiFi connected.");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
server.begin();
}
void loop(){
WiFiClient client = server.available(); // Listen for incoming clients
if (client) { // If a new client connects,
Serial.println("New Client."); // print a message out in the serial port
String currentLine = ""; // make a String to hold incoming data from the client
while (client.connected()) { // loop while the client's connected
if (client.available()) { // if there's bytes to read from the client,
char c = client.read(); // read a byte, then
Serial.write(c); // print it out the serial monitor
header += c;
if (c == '\n') { // if the byte is a newline character
// if the current line is blank, you got two newline characters in a row.
// that's the end of the client HTTP request, so send a response:
if (currentLine.length() == 0) {
// HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
// and a content-type so the client knows what's coming, then a blank line:
client.println("HTTP/1.1 200 OK");
client.println("Content-type:text/html");
client.println("Connection: close");
client.println();
// turns the GPIOs on and off
if (header.indexOf("GET /13/on") >= 0) {
Serial.println("GPIO 13 on");
output5State = "on";
digitalWrite(output5, HIGH);
} else if (header.indexOf("GET /13/off") >= 0) {
Serial.println("GPIO 13 off");
output5State = "off";
digitalWrite(output5, LOW);
} else if (header.indexOf("GET /12/on") >= 0) {
Serial.println("GPIO 12 on");
output4State = "on";
digitalWrite(output4, HIGH);
} else if (header.indexOf("GET /12/off") >= 0) {
Serial.println("GPIO 12 off");
output4State = "off";
digitalWrite(output4, LOW);
}
// Display the HTML web page
client.println("<!DOCTYPE html><html>");
client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");
client.println("<link rel=\"icon\" href=\"data:,\">");
// CSS to style the on/off buttons
// Feel free to change the background-color and font-size attributes to fit your preferences
client.println("<style>html { font-family: Helvetica; display: inline-block; margin: 0px auto; text-align: center;}");
client.println(".button { background-color: #195B6A; border: none; color: white; padding: 16px 40px;");
client.println("text-decoration: none; font-size: 30px; margin: 2px; cursor: pointer;}");
client.println(".button2 {background-color: #77878A;}</style></head>");
// Web Page Heading
client.println("<body><h1>ESP8266 Web Server</h1>");
client.println("<hr width=\"50%\" color=\"blue\"/>");
// Display current state, and ON/OFF buttons for GPIO 5
client.println("<p>GPIO 13 - State " + output5State + "</p>");
// If the output5State is off, it displays the ON button
if (output5State=="off") {
client.println("<p><a href=\"/13/on\"><button class=\"button\">ON</button></a></p>");
} else {
client.println("<p><a href=\"/13/off\"><button class=\"button button2\">OFF</button></a></p>");
}
// Display current state, and ON/OFF buttons for GPIO 4
client.println("<p>GPIO 12 - State " + output4State + "</p>");
// If the output4State is off, it displays the ON button
if (output4State=="off") {
client.println("<p><a href=\"/12/on\"><button class=\"button\">ON</button></a></p>");
} else {
client.println("<p><a href=\"/12/off\"><button class=\"button button2\">OFF</button></a></p>");
}
client.println("</body></html>");
// The HTTP response ends with another blank line
client.println();
// Break out of the while loop
break;
} else { // if you got a newline, then clear currentLine
currentLine = "";
}
} else if (c != '\r') { // if you got anything else but a carriage return character,
currentLine += c; // add it to the end of the currentLine
}
}
}
// Clear the header variable
header = "";
// Close the connection
client.stop();
Serial.println("Client disconnected.");
Serial.println("");
}
}
