0

What I did was that I wrote a piece of code that will-in-fact move a servo motor when a clap is detected using a sound impact sensor (fc-04). The code for this is seen here and in fact does work:

#include "Arduino.h"                                                            
#include <Servo.h>
Servo myservo;//create servo object to control a servo                                                                                  
enum {                                                                          
    SERIAL_BAUD        = 9600,                                                  
    SENSOR_DIGITAL_PIN =    2,                                                  
    SOUND_DELAY        =   1500, /* Delay to avoid duplicate detection */         
};                                                                              

void setup() {                                                                  
    Serial.begin(SERIAL_BAUD);                                                  
    pinMode(SERIAL_BAUD, INPUT);
    myservo.attach(9);//attachs the servo on pin 9 to servo object
    myservo.write(0);//back to 0 degrees 
    delay(1000);//wait for a second                                                
}                                                                               

void loop() {                                                                   
    if (digitalRead(SENSOR_DIGITAL_PIN) == LOW) {                               
        static int count;                                                       

        Serial.print("Sound detected: ");                                       
        Serial.println(++count);    
        myservo.write(170);//goes to 15 degrees 
        delay(3000);//wait for 3 seconds
        myservo.write(10);//back to 0 degrees 
        delay(1000);//wait for a second                                                            

        // Wait a short bit to avoid multiple detection of the same sound.      
        delay(SOUND_DELAY);                                                     
    }                                                                           
}                  

On a seperate occasion I paired two arduinos together using two hc-05 bluetooth modeules making one a slave and another a master, the initial code I used for both of them are listed here:

//                 == SLAVE CODE ==


#include <Servo.h>
#define button 8

Servo myServo;
int state = 20;
int buttonState = 0;

void setup() {
  pinMode(button, INPUT);
  myServo.attach(9);
  Serial.begin(38400); // Default communication rate of the Bluetooth module
}

void loop() {
 if(Serial.available() > 0){ // Checks whether data is comming from the serial port
    state = Serial.read(); // Reads the data from the serial port
 }
 // Controlling the servo motor
 myServo.write(state);
 delay(10);

 // Reading the button
 buttonState = digitalRead(button);
 if (buttonState == HIGH) {
   Serial.write('1'); // Sends '1' to the master to turn on LED
 }
 else {
   Serial.write('0');
 }  
}

and

//                == MASTER CODE ==

#define ledPin 9

int state = 0;
int potValue = 0;

void setup() {
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);
  Serial.begin(38400); // Default communication rate of the Bluetooth module
}

void loop() {
 if(Serial.available() > 0){ // Checks whether data is comming from the serial port
    state = Serial.read(); // Reads the data from the serial port
 }
 // Controlling the LED
 if (state == '1') {
  digitalWrite(ledPin, HIGH); // LED ON
  state = 0;
 }
 else if (state == '0') {
  digitalWrite(ledPin, LOW); // LED ON
  state = 0;
 }
 // Reading the potentiometer
 potValue = analogRead(A0);
 int potValueMapped = map(potValue, 0, 1023, 0, 255);
 Serial.write(potValueMapped); // Sends potValue to servo motor
 delay(10);
}

I attempted to use the master and slave code with the one with the servo and fc-04 so that the sound sensor will be on the master and the servo on the slave so that when ever I clap it will move the servo on the other arduino.

The new master and slave code that I used are :

//New slave
#include "Arduino.h"                                                            
#include <Servo.h>
int state = 0;
Servo myservo;

void setup() {
  Serial.begin(38400); // Default communication rate of the Bluetooth module
  myservo.attach(9);//attachs the servo on pin 9 to servo object
  myservo.write(0);//back to 0 degrees 
  delay(1000);//wait for a second 
  }


void loop() {
 if(Serial.available() > 0){ // Checks whether data is comming from the serial port
    state = Serial.read(); // Reads the data from the serial port
 }
// Controlling the servo
 if (state == '1') {
  myservo.write(170);//goes to 15 degrees 
  delay(3000);//wait for 3 seconds
  myservo.write(10);//back to 0 degrees 
  delay(1000);//wait for a second
  state = 0;
 }
 else if (state == '0') {
  state = 0;
  }  
}

//new Master 
#include "Arduino.h"
#include <SoftwareSerial.h>
int state = 0;
SoftwareSerial BTserial(1, 0); // RX | TX                       

void setup() {                                                                  
    Serial.begin(9600);                                                  
    pinMode(9600, INPUT);
    BTserial.begin(38400);

}

void loop() {                                                                   
    if (digitalRead(2) == LOW) {                               
        static int count; 
        BTserial.write('1');
        delay(1500);
    }
    else {
      BTserial.write('0');
    }
}

However the slave and master code for the servo and fc-04 is not working at all despite knowing that all the conponents work individually. What I am aware of is that the fc-04 uses serial communication to transfer data and so does the hc-05 bluetooth modules. This causes an issue because I believe from experience is that you can not have two serial communications being transmitted from the arduino at the same time which I need. I have been at this for days and It is driving me nuts. If I could have some help at all I will be much appreciated.

1

SoftwareSerial BTserial(1, 0); // RX | TX

Well, there's your problem. You are starting SoftwareSerial on the Serial pins. Don't do that!

For best results, hook your BT to pins 8 & 9 and use AltSoftSerial. It is much more efficient than SoftwareSerial, and it will not interfere with Serial reads and writes.

If you really can't use those pins, pick two other pins and use my NeoSWSerial. It is almost as efficient, and it works on any PinChange interrupt pins at 9600, 19200 or 38400 baud rates.

  • Gotcha , so because of what I was doing it causes crosstalk then. When I have the chance tomorrow I will make the required changes and report back on the results. Thanks – blawrence Mar 6 '17 at 22:56

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.