Processing/Bluetooth to Arduino - bluetooth

Question

I want to light up a LED wirelessly through processing.
what I have so far.
I can (wirelessly) turn on my LED using a serial terminal called "Bluterm".
I can turn on my LED by pressing 1 or 0 to switch LED on and off in processing.
How can I leave Bluterm out of my equation and use processing to send the 1 and 0 through bluetooth.
Here is my code for processing:
import processing.serial.*;
Serial port;
String string;
void setup(){
String portName = Serial.list()[2]; //change the 0 to a 1 or 2 etc. to match your port
port = new Serial(this, portName, 9600);
port.bufferUntil('\n');
}
void draw() {
printArray(string);
}
void keyPressed() {
if (key =='1'){port.write('1');}
if (key=='0') {port.write('0');}
}
void serialEvent(Serial port) {
string = port.readStringUntil('\n');}
and the Arduino code
char data;
int led = 13;
void setup() {
pinMode(led, OUTPUT);
Serial.begin(9600);
}
void loop() {
if (Serial.available()>0){
data = Serial.read();
}
if (data=='1'){
Serial.println("HELLO");
digitalWrite(led, HIGH);
}
else if (data=='0'){
digitalWrite(led, LOW);
Serial.println("BYE");}
}
I'm kind of lost, can processing talk to bluetooth or do I always need a terminal?
If something isn't clear pls don't hesitate to ask,
Thank you for your time,
Juriaan

Answer 1

The Processing code makes sense.
It could do with a bit of formatting and error checking, but it's all pretty much there:
import processing.serial.*;
Serial port;
String string = "";
void setup() {
String portName = Serial.list()[2]; //change the 0 to a 1 or 2 etc. to match your port
try{
port = new Serial(this, portName, 9600);
port.bufferUntil('\n');
}catch(Exception e){
e.printStackTrace();
}
}
void draw() {
background(0);
text(string,10,15);
}
void keyPressed() {
if(port != null){
if (key =='1') {
port.write('1');
}
if (key=='0') {
port.write('0');
}
}
}
void serialEvent(Serial port) {
string = port.readString();
if(string == null){
println("null serial string");
string = "";
}
}
The Arduino code looks legit too.
What's unclear is what Bluetooth module you're using and how you're setting it up.
For example, if you're using something like BlueSmirf, be sure to use the guide
supplied.
The main points are:
Make sure you're using the SerialPortProfile (SPP) Bluetooth Profile
Double check you're wiring: the way your Arduino code reads you would be connect BT module's TX to Arduino's RX pin 0 and BT module's RX pin to Arduino's TX pin 1. Note you may want to do that after you upload your firmware with Arduino (as pin's 0 and 1 are Arduino's hardware Serial), otherwise goto point 3 :) (recommeded)
If you use an Arduino with multiple hardware serial ports (like Arduino mega) go with those (e.g. Serial1 instead of Serial) otherwise use a SoftwareSerial library with a low baud rate (like 9600), avoiding high baud rates.
Update
The HC-05 module uses 3.3V logic, while the Arduino uses 5V logic.
Uses a bidirectional 3.3V <-> 5V logic level converter or resistors, otherwise you risk frying your HC-05 module:
A quick search returns a detailed HowToMechatronics.com Arduino and HC-05 Bluetooth Module Tutorial

Answer 2

i see u are using a hc05 bluetooth device i have this myself but i dont really get what u want to use for sending the 1 and 0 to your hc05 and are you only using a led becouse if it is i would be able to help on (if you wanna send the bluetooth signals with a mobile app try the blynk app fron app store or google play store)