Develop Reference

How to detect if a device get my phone bluetooth name?

I'm using a bluetooth modul (HC-05) to detect if an android phone is in the modul's range.
I tried to connect with HC-05 (as master) and a PIC16f887 to the phone, but I can't. Searched many pages on net how to use HC-05 as master, but no solution.
So, finally I could do this by modul get my phone's BT name. If it could, my phone is in range.
But now I want my phone to detect this "remote name query" and play some sound then.
Sorry for my poor english :)

Im guessing you want something like this: VIDEO
Lets start with the basics:
The typical default factory settings for a new Bluetooth HC-05 module are:
Default Bluetooth Name: “HC-05”
Default Password: 1234 or 0000
Default Communication: Slave Device
Default Mode: Data Mode
Default Data Mode Baud Rate: 9600, 8, N, 1
Default Command Mode Baud Rate: 38400, 8, N, 1
Default firmware: LINVOR
1. To TEST Bluetooth connections from your android device use id suggest you use this APK
2. Connect the HC-05 BT module as shown in the diagram
3. Initialize the UART receiver at the microcontroller end (side)
(code includes 2 leds for pin 33 and pin 34)
/*
* LAB Number: 17
* LAB Name: Bluetooth Module HC-05 Interfacing (Smartphone -> MCU)
* Author: Khaled Magdy
* For More Information Visit My Website # DeepBlueMbedded.com
*
*/
#include <xc.h>
#include <stdint.h>
#include "config.h"
#define _XTAL_FREQ 4000000
//--[ Control Data ]--
#define Blue_LED_ON 49
#define Blue_LED_OFF 50
#define Yellow_Toggle 51
//--------------------------------
// Functions Declarations
void UART_RX_Init(void);
// Globals
uint8_t UART_Buffer = 0;
//--------------------------------
// Main Routine
void main(void)
{
//--[ Peripherals & IO Configurations ]--
UART_RX_Init(); // Initialize The UART in Master Mode # 9600bps
TRISB0 = 0; // Blue LED (Switch)
TRISB1 = 0; // Yellow LED (Toggle)
RB0 = 0; // Initially OFF
RB1 = 0; // Initially OFF
//---------------------------
while(1)
{
}
return;
}
//--------------------------------
// Functions Definitions
void UART_RX_Init()
{
BRGH = 1; // Set For High-Speed Baud Rate
SPBRG = 25; // Set The Baud Rate To Be 9600 bps
// Enable The Ascynchronous Serial Port
SYNC = 0;
SPEN = 1;
// Set The RX-TX Pins to be in UART mode (not io)
TRISC6 = 1; // As stated in the datasheet
TRISC7 = 1; // As stated in the datasheet
//--[ Enable UART Receiving Interrupts ]--
RCIE = 1; // UART Receving Interrupt Enable Bit
PEIE = 1; // Peripherals Interrupt Enable Bit
GIE = 1; // Global Interrupt Enable Bit
//------------------
CREN = 1; // Enable Data Continous Reception
}
void interrupt ISR (void)
{
if (RCIF == 1)
{
UART_Buffer = RCREG; // Read The Received Data Buffer
// This could have been done within the main loop. Since it's not
// Excessive processing, so it's OK to do it here below
if(UART_Buffer == Blue_LED_ON)
RB0 = 1; // Blue LED ON
if(UART_Buffer == Blue_LED_OFF)
RB0 = 0; // Blue LED OFF
if(UART_Buffer == Yellow_Toggle)
RB1 = ~RB1; // Toggle Yellow LED
RCIF = 0; // Clear The Interrupt Flag
}
}
NOTE The Data Bytes (49, 50, and 51) are the ASCII equivalents for the numeric characters (1, 2, and 3 respectively).
4. Download this apk to send commands to your HC05: APK
For more info follow Reference: LINK

HC-06 Bluetooth to Android - Receiving Random Symbols

I wanted to send values from a light sensor, using an HC-06. I have everything connected properly. I used MIT App Inventor and the image shows how I connect to the Bluetooth module, and how do I show the data.
Arduino Code
int analogInPin = A0;
int sensorValue = 0;
void setup() {
Serial.begin(9600);
}
void loop() {
sensorValue = analogRead(analogInPin);
Serial.println(sensorValue);
delay(100);
}
Phone
I already searched for several solutions but none worked. I have the baud rate at 9600 (the same as the Bluetooth module).

How to exit void loop in Arduino if there is no serial data available?

I am building an internet controlled robot that uses 2 android phones for controlling.
The first phone is connected to Arduino Uno via USB and serves as a 3G shield
The second phone is used to control the whole thing. It sends unassigned byte to the first phone which sends it to Arduino.
The apps I uses on the phones have one problem. The joystick in the app doesn't send a specific command when its in rest. For example when I move it up it sends "1" to the phone connected to the Arduino which drives the motors forward but when I release the joystick it stops sending data however the motors on my robot still spin until I move the joystick down which sends "2" motor.run(RELEASE);
How can I stop the motors if there is no Serial Data available?
This is the code i wrote.
#include <AFMotor.h>
AF_DCMotor motor_left(2, MOTOR12_1KHZ);
AF_DCMotor motor_right(3, MOTOR12_1KHZ);
int ledPin = 13;
int speed_min = 100; //the minimum "speed" the motors will turn - take it lower and motors don't turn
int speed_max = 1000; //the maximum "speed" the motors will turn – you can’t put in higher
int speed_left = speed_max; // set both motors to maximum speed
int speed_right = speed_max;
int command = 0;
void setup ()
{
Serial.begin(9600);
pinMode(ledPin, OUTPUT);
motor_left.setSpeed(255);
motor_left.run(RELEASE);
motor_right.setSpeed(255);
motor_right.run(RELEASE);
motor_left.setSpeed(speed_left); // minimum speed 135 max speed 255
motor_right.setSpeed(speed_right); // minimum speed 135 max speed 255
}
void loop() {
if (Serial.available() > 0);
byte command = Serial.read();
if (command == 1)
{
Serial.println("Move Forward");
digitalWrite(ledPin, HIGH);
motor_left.run(FORWARD);
}
if (command == 2)
{
Serial.println("Stop");
digitalWrite(ledPin, LOW);
motor_left.run(RELEASE);
}
}
So basically it should do nothing if there is no data available.

Use your code like this, it will help
void loop() {
if (Serial.available() > 0) {
byte command = Serial.read();
if (command == 1) {
Serial.println("Move Forward");
digitalWrite(ledPin, HIGH);
motor_left.run(FORWARD);
} else if (command == 2) {
Serial.println("Stop");
digitalWrite(ledPin, LOW);
motor_left.run(RELEASE);
} else {
//put your code to stop Motor
}
}
}

control a servo with android and arduino

I'm trying to control a servo with an android phone and an arduino via bluetooth but the data in the arduino is received as a char, and the arduino doesn't know when all the data is received and the servo don't move properly. The arduino code is this:
#include
Servo myservo;
char val; // variable to receive data from the serial port
int ledpin = 13; // LED connected to pin 48 (on-board LED)
void setup() {
pinMode(ledpin, OUTPUT); // pin 48 (on-board LED) as OUTPUT
Serial.begin(9600); // start serial communication at 9600bps
myservo.attach(9);
}
void loop() {
if( Serial.available() ) // if data is available to read
{
val = Serial.read(); // read it and store it in 'val'
}
if( val - 0 >= 0 && val - 0 <= 180){
}
// Serial.print("Recibido");
delay(100); // wait 100ms for next reading
}
What can I do to get the correct value from "val" to control the servo?

You can send multiple chars if you need them. Simple store each new char into an array and program your android program to send a specific byte that indicates the ending of the val reading.
Checking this "ending" byte each time you perform a read from serial will tell you if this char is to store or to convert the previous stored chars into an integer or whatever data type you need it.
Than simply converting that array will tell you the correct val.

Arduino: using Serial and Software Serial with bluetooth module

My purpose is to use Arduino to set up communication between a PC and an Android device using an HC-05 bluetooth module.
I use the USB communication between the PC and the Arduino (Serial Monitor) and a SoftwareSerial to connect to the HC-05.
My problem is that the communication works well from BT to the PC, but doesn't work as expected in the other way. When sending from the PC to BT all the characters sent are received by the BT device only when I close the Serial Monitor on the PC or when I reset the Arduino.
I've excluded a problem with the BT Module or the Android application because if in Arduino I implement an "ECHO" code (write in Android and the send in Android) everything works fine.
With the Arduino code posted below the expected behaviour is: Arduino reset-> Hello word sent, Serial monitor opened-> nothing happens, character written on serial monitor-> character received on BT, character written on BT-> character received on Serial Monitor, Serial monitor closed-> nothing happens.
The real behaviour is: Arduino reset-> Hello word sent, Serial monitor opened-> 2 Hello word on BT and 1 ("goodnight") on PC, character written on serial monitor-> nothing, character written on BT-> character received on Serial Monitor, Serial monitor closed-> previous written character(s) in serial monitor received + Hello Word.
How can I fix this problem?
Code:
#include <SoftwareSerial.h>
SoftwareSerial mySerial(2, 3); // RX, TX
int a=0;
char c;
char d;
void setup() {
Serial.begin(9600);
Serial.println("Goodnight moon!");
mySerial.begin(9600);
mySerial.println("Hello, world?");
}
void loop() {
delay(10);
if (Serial.available()) {
c=Serial.read();
delay(10);
Serial.write(c);
}
delay(10);
if (mySerial.available()) {
d=mySerial.read();
delay(10);
mySerial.write(d);
}
}

This code is working for me on an Arduino Mini Pro (should be the same as UNO) with an HC-05. I have the HC-05 paired with my laptop. Using HyperTerminal on the COM port associated with the HC-05 and the Arduino serial console, I can send messages bidirectionally. The Serial.println statements show up in the Hyperterminal window like they should.
#include <SoftwareSerial.h>
#define rxPin 8
#define txPin 7
SoftwareSerial mySerial(rxPin, txPin); // RX, TX
char myChar ;
void setup() {
Serial.begin(9600);
Serial.println("Goodnight moon!");
mySerial.begin(9600);
mySerial.println("Hello, world?");
}
void loop(){
while(mySerial.available()){
myChar = mySerial.read();
Serial.print(myChar);
}
while(Serial.available()){
myChar = Serial.read();
mySerial.print(myChar);
}
}

I have implemented a serial communication between Arduino Uno and PC and this was my code, hope it can help:
int data;
char character;
int start_flag = 0;
void setup() {
Serial.begin(921600);
pinMode(2, OUTPUT);
}
void loop() {
if(Serial.available() > 0){
character = (char) Serial.read();
if(character == 's') {
start_flag = 1;
}
if(character == 't') {
start_flag = 0;
}
}
if (start_flag == 1) {
Serial.print(data); //data that was acquired by internal ADC
}
}

You could try this. It's about the simplest code you can use when testing Arduino bluetooth <-> C# communication. Note: the code was tested by connecting PIN1(TX) <-> MODULE RX, PIN2(RX) <-> MODULE TX and dividing the PIN1(TX) 5V to 2,5V before feeding it to the module.
Hope this helps all that are trying this!

Use this serial setup. With this code I can receive and send date to bluetooth from Serial Monitor
void setup(){
Serial.begin(9600); // Begin the serial monitor at 9600bps
bluetooth.begin(115200); // The Bluetooth Mate defaults to 115200bps
bluetooth.print("$"); // Print three times individually
bluetooth.print("$");
bluetooth.print("$"); // Enter command mode
delay(100); // Short delay, wait for the Mate to send back CMD
bluetooth.println("U,9600,N"); // Temporarily Change the baudrate to 9600, no parity
// 115200 can be too fast at times for NewSoftSerial to relay the data reliably
bluetooth.begin(9600); // Start bluetooth serial at 9600
pinMode(led, OUTPUT);
pinMode(buttonPin1, INPUT);
pinMode(buttonPin2, INPUT);
}
For more information, visit
http://www.circuitmagic.com/arduino/arduino-and-bluetooth-hc-06-to-control-the-led-with-android-device/

I recommend to use this app for testing:
https://play.google.com/store/apps/details?id=com.vagoscorp.virtualterminal
It let you see and send bytes as bytes(number from 0b00000000 to 0b11111111 (0 to 255 in decimal))
so you can make a simple echo firmware to test if your baudrate is correct and with that working, begin sending commands to turn on/off some LEDs
this is an echo code example:
char dato = 0;
void setup() {
Serial.begin(9600);//9600 is the default baudrate of the HC-05 (you can change it by AT commands, google it if you want)
//pinMode(13, OUTPUT); //enable this pin if you want to use de LED idea
//digitalWrite(13, HIGH);
}
//////////////////////////////////////////////////////////////////////////
void serialEvent() { //if you have received serial data
while (Serial.available() > 0) {
char dato = (byte)Serial.read();//save the byte
Serial.write(dato);//send the just received byte (echo)
}
}
///////////////////////////////////////////////////////////////////////////
void loop() {
}
I hope it helps you

Had the same problem, you have to view the BT module as 2 different baud rates on the wired side and the radio side. The radio side is set by whatever you connect at through putty, the wired side is programmed via AT commands. HC-05 defaults at 38400.