[Arduino]WizFi250 Twitter Example

[Arduino]WizFi250 Twitter Example

Step 1 : 구성도

Arduino에서 Reference 하는 예제는 Twitter Server에 직접 접속하는 구조가 아닌, 별도의 Proxy Server를 이용하여 Twitter Server에 접속하여 Message를 Post 한다. 참고로 본 포스팅에서 사용하는 Proxy Server는 arduino-tweet.appspot.com 이며 Post는 1분에 한번 씩 가능 하다.
Twitter Server에 직접 접속하기 위해서는 SSL Protocol 이 필요하며, 추후에 WizFi250의 SSL 기능을 이용하여 Twitter에 직접 접속하는 예제를 구현할 예정이다.
본 포스팅 예제의 구성도는 아래와 같다.

Step 2 : Get a token to post a message using OAuth

• http://arduino-tweet.appspot.com/oauth/twitter/login

  

  
  

  

  
  

  

Step 3 : Hardware

• Arduino Mega, WizFi250-EVB
  

  

• WIZnet에서는 SPI 인터페이스 기반의 Arduino Library를 제공하며, 아래 경로에서 다운로드 할 수 있다.
  • https://github.com/Wiznet/Arduino_WizFi250
• WizFi250을 Arduino와 사용하기 위해서는 아래 포스팅을 참고 하기 바란다.
  • WizFi250-EVB(Arduino Shield) 이용 시, Check 사항

Step 4 : Software

아래 예제는 https://github.com/Wiznet/Arduino_WizFi250의 Software/WizFi250/Example/WizFi250_Twitter 폴더에 있다.

#include <Arduino.h>
#include <SPI.h>
#include <IPAddress.h>
#include "WizFi250.h"
#include "WizFi250_tcp_client.h"

#define SSID    "WiznetKaizen"
#define KEY     "qazxswedc"
#define AUTH    ""

#define REMOTE_PORT 80
#define TOKEN "Your-Token"    // For Wiznet_Maker

#define LIB_DOMAIN "arduino-tweet.appspot.com"

char server[] = LIB_DOMAIN;
unsigned long lastConnectionTime = 0;
const unsigned long postingInterval = 60000;

boolean Wifi_setup = false;
boolean lastConnected = false;
boolean isFirst = true;

WizFi250        wizfi250;
WizFi250_TCP_Client myClient(server, REMOTE_PORT);

//The setup function is called once at startup of the sketch
void setup()
{
    // Add your initialization code here
    String str;
    char ssid[50],key[50];

    Serial.begin(9600);
    Serial.println("\r\nSerial Init");

    wizfi250.begin();
    wizfi250.setDebugPrint(4);
    wizfi250.hw_reset();

    wizfi250.sync();
    wizfi250.setDhcp();

    Serial.println("Input SSID");
    str = getStr();
    str.toCharArray(ssid,50);
    Serial.println("Input KEY");
    str = getStr();
    str.toCharArray(key,50);

    for(int i=0; i<10; i++)     // Try to join 30 times
    {
        if( wizfi250.join(ssid,key,AUTH) == RET_OK )
        {
            Wifi_setup = true;
            break;
        }
    }
}

void loop()
{
    if( Wifi_setup )
    {
        wizfi250.RcvPacket();

        if( myClient.available() )
        {
            char c = myClient.recv();
            if( c != NULL )
                Serial.print(c);
        }
        else
        {
            if( !myClient.getIsConnected() && lastConnected )
            {
                Serial.println();
                Serial.println("disconnecting.");
                myClient.stop();
            }


            if( isFirst || (((millis() - lastConnectionTime) > postingInterval) && (!myClient.getIsConnected())) )
            {
                Serial.println("Ready to transmit message");
                Twitter_Post( inputSerialMessage() );
                isFirst = false;
            }

            lastConnected = myClient.getIsConnected();
        }
    }
}

String inputSerialMessage()
{
    String SendingMessage="";

    Serial.print("Input Your Name :");
    SendingMessage  = "Name : ";
    SendingMessage += getStr();
    SendingMessage += "\r\n";

    Serial.print("Input Your Comment :");
    SendingMessage += "Comment : ";
    SendingMessage += getStr();
    SendingMessage += "\r\n";

    return SendingMessage;
}


String getStr()
{
    String str="";

    while(1)
    {
        if( Serial.available() )
        {
            char inChar = (char)Serial.read();
            Serial.print(inChar);

            if(inChar == '\r')   break;
            str += inChar;
        }
    }
    return str;
}


bool Twitter_Post(String thisData)
{
    uint8_t content_len[6]={0};
    String TxData;
    uint16_t length;

    Serial.println("Connecting..");
    if(myClient.connect() == RET_OK)
    {
        TxData  = "POST http://";
        TxData += LIB_DOMAIN;
        TxData += "/update HTTP/1.0\r\n";
        TxData += "Content-Length: ";

        length = thisData.length() + strlen(TOKEN) + 14;
        itoa(length, (char*)content_len, 10);

        TxData += (char*)content_len;
        TxData += "\r\n\r\n";
        TxData += "token=";
        TxData += TOKEN;
        TxData += "&status=";
        TxData += thisData;
        TxData += "\r\n";

        Serial.print(TxData);
        myClient.send((String)TxData);

        lastConnectionTime = millis();
    }
}

5 Demo

1. 환경 설정

Linux Terminal 설정

• minicom 실행

• Serial setup
• dmesg | grep tty를 수행하면 linux 상에서 사용 중인 Serial Port를 확인 할 수 있다.

2. 실행 화면

AT+WNET=1
[OK]
Input SSID

Input KEY
qazxswedc
<Send AT Command>
AT+WLEAVE
[OK]
<Send AT Command>
AT+WSET=0,WiznetKaizen
[OK]
<Send AT Command>
AT+WSEC=0,,qazxswedc
[OK]
<Send AT Command>
AT+WJOIN
Joining : WiznetKaizen
Successfully joined : WiznetKaizen
[Link-Up Event]
  IP Addr    : 192.168.201.12
  Gateway    : 192.168.201.1
[OK]Ready to transmit message
Input Your Name : WizFi250
Comment : Hi I am WizFi250
Connecting..

<Send AT Command>
AT+FDNS=arduino-tweet.appspot.com,1000
74.125.203.141
[OK]
<Send AT Command>
AT+SCON=O,TCN,74.125.203.141,80,,0
[OK]
[CONNECT 0]POST http://arduino-tweet.appspot.com/update HTTP/1.0
Content-Length: 111

token=2815954261-XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:status=Name : WizFi250
Comment : Hi I am WizFi250


<Send AT Command>
AT+SSEND=0,0.0.0.0,80,191
[0,,,191]
[OK]HTTP/1.0 200 OK
Content-Type: text/html; charset=utf-8
Cache-Control: no-cache
Vary: Accept-Encoding
Date: Tue, 23 Sep 2014 04:03:08 GMT
Server: Google Frontend
Alternate-Protocol: 80:quic,p=0.002

OK<Disassociate>

disconnecting.

3. Twitter 계정에서 메시지 확인