This script utilises an Arduino with an ethernet and RGB shield, plus a 16x2 LCD screen. The Arduino can be connected to a router and reached from a local IP or it will function on a direct ethernet connection if the machine connected is configured correctly. No DHCP functionality is added to the script and it relies on a static IP. The main .ino file relies on a secondary config.h file, and if they are in the same folder the Arduino IDE will open them both in separate tabs and compile them together.
The pin inputs for the RGB shield are numbered on the board. They need to be initialised before use.
int RED = 3;
int GREEN = 5;
int BLUE = 6;
This standardMessage value sets the standard LCD output for the second line of a 16x2 screen. The three standard RGB integers set the colour that the LEDs revert to.
String standardMessage = "VPW Systems";
int standardRed = 250;
int standardGreen = 166;
int standardBlue = 26;
The network configuration for the Arduino happens here. Most of these values can be commented out and should auto configure.
IPAddress ip(192, 168, 1, 177);
IPAddress myDns(192,168,1, 1);
IPAddress gateway(192, 168, 1, 1);
IPAddress subnet(255, 255, 255, 0);
EthernetServer server(80);
A simple HTML page exists on the webserver with the existing sequences. This is extremely useful for adding new functions and troubleshooting so if new sequences are added, an entry like the one below should also be added in RGBETHLCD.ino:
client.println("<a href=\"/?redon\"\">Turn On RED LED</a>");
client.println("<br />");
Adding a new sequence is done by writing an if statement directly into the script. Here is an example of a flashing sequence:
if (readString.indexOf("?sequence1") >0){
lcd.clear();
lcd.print(ip);
lcd.setCursor (0,1);
lcd.print("Sequence 1");
for (repeats = 10; repeats > 0; repeats --) {
analogWrite(RED, 255);
analogWrite(GREEN, 0);
analogWrite(BLUE, 0);
delay(500);
analogWrite(RED, 0);
analogWrite(GREEN, 0);
analogWrite(BLUE, 0);
delay(500);
}
analogWrite(RED, standardRed);
analogWrite(GREEN, standardGreen);
analogWrite(BLUE, standardBlue);
lcd.clear();
lcd.print(ip);
lcd.setCursor (0,1);
lcd.print(standardMessage);
}
This sequence, triggered when the url http://$ArduinoIP/?sequence1 is requested, flashes red on and off every half second for 10 repeats, making the sequence 10 seconds long. It also displays a custom message on the second line of the LCD. The for statement starts with a value for repeats of 10 and counts down to 1. After the 10 repeats, it returns to the standard RGB output and the standard LCD output.
This is an example of a fading sequence:
if (readString.indexOf("?sequence4") >0){
lcd.clear();
lcd.print(ip);
lcd.setCursor (0,1);
lcd.print("Sequence 4");
for (repeats = 15; repeats > 0; repeats --) {
for (brightness = 0; brightness < 255; brightness ++) {
analogWrite(RED, brightness);
analogWrite(GREEN, brightness);
analogWrite(BLUE, brightness);
delay(5);
}
for (brightness = 255; brightness > 0; brightness --) {
analogWrite(RED, brightness);
analogWrite(GREEN, brightness);
analogWrite(BLUE, brightness);
delay(5);
}
}
analogWrite(RED, standardRed);
analogWrite(GREEN, standardGreen);
analogWrite(BLUE, standardBlue);
lcd.clear();
lcd.print(ip);
lcd.setCursor (0,1);
lcd.print(standardMessage);
}
First the LCD display is cleared, set to the IP address on the first line and the custom second line. This fading sequence uses two separate for loops inside a for loop. The first for loop has 255 repeats, each repeat incrementing the brightness by 1. This changes the value of RED and GREEN but BLUE stays off. The second for loop starts with a brightness of 255 and increments brightness by negative 1, causing the LEDs to fade. These two for loops are repeated 15 times, and then the LEDs are set back to the standard value and the LCD back to the standard output.
When adding a new sequence, consider adding a return to the standard value of RGB outside of the loop. Sequences are most useful when limited to a certain time period otherwise the alert loses its effectiveness. The standard output uses variables set in the config.h file.
analogWrite(RED, standardRed);
analogWrite(BLUE, standardBlue);
analogWrite(GREEN, standardGreen);
In a similar fashion, the LCD should be wiped and reverted to the standard output at the end of the sequence outside the loop.
lcd.clear();
lcd.print(ip);
lcd.setCursor (0,1);
lcd.print(standardMessage);
When writing sequences, note that delay is in milliseconds. Large values such as 500 are for flashing sequences and a smaller value such as 5 is used for fading sequences.
The HTML page hosted on the webserver is useful for testing new sequences. When that isn't working, the Arduino IDE has a Serial Monitor that shows HTTP requests and the IP of the board. All HTTP requests can be sent to the Serial Monitor with this commented out line in the loop:
//Serial.print(c);