Arduino でサーバーから情報を取得して結果を LCD の LiquidCrystal から出力します。
使用機材
| 項目 | 機材名 |
|---|---|
| 使用しているArduino | arduino nano |
| 書き込みブートローダ | atmega328old |
| LAN シールド | ENC28J60 |
| LCDディスプレイ | 16 x 2 の LiquidCrystal ( I2C 付き ) |
GPIO端子の接続設定
|センサー端子|Arduino端子|
|---|---|---|
|SDA|A4|
|SDL|A5|
|VCC|5V|
|GND|GND|
ソースコードはこちら
たまにサーバーへの接続が失敗しますので、その時は再起動を行ってみてください。
I2CLiquidCrystalDisplay.ino
//=================================================================================
// I2C Scanner scan i2c address (ex 0x27
//=================================================================================
// Written by Nick Gammon
// Date: 20th April 2011
/*
# include <Wire.h>
void setup() {
Serial.begin (9600);
Serial.println ("I2C scanner. Scanning ...");
byte count = 0;
Wire.begin();
for (byte i = 8; i < 120; i++){
Wire.beginTransmission (i);
if (Wire.endTransmission () == 0){
Serial.print ("Found address: ");
Serial.print (i, DEC);
Serial.print (" (0x");
Serial.print (i, HEX);
Serial.println (")");
count++;
delay (1); // maybe unneeded?
}
}
Serial.println ("Done.");
Serial.print ("Found ");
Serial.print (count, DEC);
Serial.println (" device(s).");
}
void loop() {}
*/
//=================================================================================
// New-LiquidCrystal Please download and unziped files into Arduino/Libraries
//
// fmalpartida/New-LiquidCrystal: Clone of the new liquid crystal library from:
// https://bitbucket.org/fmalpartida/new-liquidcrystal https://github.com/fmalpartida/New-LiquidCrystal
//=================================================================================
// LCD setting
# include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd( 0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); // Set the LCD I2C address, if it's not working try 0x27.
// LCD customize character
// https://maxpromer.github.io/LCD-Character-Creator/
byte musictone[8] = { // ♪
B01100,
B01010,
B01001,
B01001,
B01010,
B11000,
B11000,
};
byte checkmark[8] = { // チェックマーク
B00001,
B00001,
B00010,
B00010,
B10100,
B11100,
B01000,
B00000
};
// LAN setting
# include <UIPEthernet.h>
byte mac[] = { 0x90, 0xA2, 0xDA, 0x0D, 0x78, 0xEE };
IPAddress ip(192, 168, 0, 117);
IPAddress myDns(192, 168, 0, 1);
EthernetClient client;
// setting server's ip address
char server[] = "192.168.0.104";
// init function
void setup(){
// for usb serial print
Serial.begin(9600);
// LCD init
lcd.begin(16,2); // iInit the LCD for 16 chars 2 lines
lcd.backlight(); // Turn on the backligt (try lcd.noBaklight() to turn it off)
//lcd.autoscroll();
// LCD add my character
lcd.createChar(1, musictone);
lcd.createChar(2, checkmark);
// LCD start my message
lcd.setCursor(0,0); //First line
lcd.print("Get From Server");
lcd.setCursor(0,1); //Second line
lcd.print("Now Loading....");
// LAN start
delay( 1000 );
Ethernet.begin(mac, ip , myDns );
delay( 1000 );
// LAN show my ip addresses
/*
Serial.print("localIP: ");
Serial.println(Ethernet.localIP());
Serial.print("subnetMask: ");
Serial.println(Ethernet.subnetMask());
Serial.print("gatewayIP: ");
Serial.println(Ethernet.gatewayIP());
Serial.print("dnsServerIP: ");
Serial.println(Ethernet.dnsServerIP());
*/
// get server's data
Serial.println("Connecting...");
if (client.connect(server, 80)) {
Serial.println("Connected");
// Make a HTTP request:
client.println("GET /1.php HTTP/1.1");
client.println("Host: 192.168.0.104" );
client.println("Connection: close");
client.println();
}
// get server's data failed
else {
Serial.println("connection failed");
lcd.setCursor(0,1); //Second line
lcd.print("Failed Pls Rebot");
//lcd.autoscroll(); ?
//lcd.print("Failed please reboot");
}
delay( 1000 );
}
// while( 1 )
void loop(){
// character settings
char c;
long c_index = 0;
boolean is_c_blank = true;
// LCD show my message
lcd.setCursor(0,0);
lcd.print("SV:" + String( server ) );
// read server's data
//Serial.println( "----------header start --------" );
while (client.connected()) {
if (client.available()) {
c = client.read();
// check c not blank
if (c == '\n' && is_c_blank) {
//Serial.println( "----------header end --------" );
// get server's body data into result[ ]
//Serial.println( "----------body start --------" );
char result[ ] = " ";
while (client.connected()) {
if (client.available()) {
c = client.read();
// add text into result[ ] if not \n
if( c != '\n' ){
Serial.print( c );
result[c_index] = c ;
c_index ++;
}
}
}
//Serial.println( "----------body end --------" );
//Serial.println( result );
// LCD print my result[]
lcd.setCursor(0,1);
lcd.write(2); // my custom character
lcd.print(result);
break;
}
// check c data if \n
if (c == '\n') {
is_c_blank = true;
}
else if (c != '\r') {
is_c_blank = false;
}
}else{
break;
}
}
}
サーバー側のコード
1.php
<?php
echo " result ";
for ($i=0; $i<6; $i++) {
$d=rand(1,30)%2;
echo $d ? chr(rand(65,90)) : chr(rand(48,57));
}
LiquidCrystal の autoscroll とか使えば結構遊べるかと思います。
Facebookのイイネの数や日経平均株価を表示しても面白いでしょう。
jsonでの取得はそのうち