Serial Communications Bluetooth help

Projects Networking, Protocols, and Devices
1

Hi,

I am trying to figure out how to communicate with the Arduino using bluetooth, first I found and modified a program that uses my PC's serial port and the program worked as expected. This is the code:

#include <SoftwareSerial.h>

int readByte;

char bytes[20];

int i = 0;
int eol = 13;    // carriage return
boolean readSomething = false;

SoftwareSerial softwareSerial(7, 6);

void setup() {
  Serial.begin(57600);
  delay(300);
  Serial.println("\nBluetooth Ready.");
  Serial.println("Waiting...");
  Serial.println("");
  delay(1000);
}

void loop() {
  //Serial.listen();
  long l = millis();
  while (millis() - l < 1000) {
    while (Serial.available() > 0) {
      readByte = Serial.read();
      bytes[i] = readByte;
      Serial.print(bytes[i]);
      if ( bytes[i] == eol ) i--;
      i++;
      readSomething = true;
    }
  }

  if (readSomething == true) {
    delay(20);
    readSomething = false;
    for (int c = 0; c < i; c++) {
      Serial.println("");
      Serial.print(c);
      Serial.println(" <-- index");
      Serial.print(bytes[c]);
      Serial.println(" <-- single");
      Serial.print("Print Bytes = ");
      Serial.println(bytes);
      Serial.print("Write Bytes = ");
      Serial.write(bytes);
      Serial.println("");
      Serial.println("------------------");
    }
    
    for (int z = 0; z < 21; z++) {
      bytes[z] = 0;
      Serial.print(z);
    }
    Serial.println("");
    i = 0;
  } 
}

I then modified the program for bluetooth communications, I am using a bluesmirf gold device and an android phone using a terminal emulator app. When I use singe character inputs, it works as expected, but when I send 'hello' the program stores diffent characters in my 'bytes' variable. Here is the code.

#include <SoftwareSerial.h>

int readByte;

char bytes[20];

int i = 0;
int eol = 13;    // carriage return
boolean readSomething = false;

SoftwareSerial softwareSerial(7, 6);

void setup() {
  softwareSerial.begin(115200);
  delay(300);
  softwareSerial.println("\nBluetooth Ready.");
  softwareSerial.println("Waiting...");
  softwareSerial.println("");
  delay(1000);
}

void loop() {
  softwareSerial.listen();
  long l = millis();
  while (millis() - l < 1000) {
    while (softwareSerial.available() > 0) {
      readByte = softwareSerial.read();
      bytes[i] = readByte;
      softwareSerial.print(bytes[i]);
      //delay(10);
      if ( bytes[i] == eol ) i--;
      i++;
      readSomething = true;
    }
  }

  if (readSomething == true) {
    delay(20);
    readSomething = false;
    for (int c = 0; c < i; c++) {
      softwareSerial.println("");
      softwareSerial.print(c);
      softwareSerial.println(" <-- index");
      softwareSerial.print(bytes[c]);
      softwareSerial.println(" <-- single");
      softwareSerial.print("Print Bytes = ");
      softwareSerial.println(bytes);
      softwareSerial.print("Write Bytes = ");
       softwareSerial.write(bytes);
      softwareSerial.println("");
      softwareSerial.println("------------------");
    }
    for (int z = 0; z < 21; z++) {
      bytes[z] = 0;
      softwareSerial.print(z);
    }
    softwareSerial.println("");
    i = 0;
  } 
}

Do I need to configure my bluetooth device differently? or do I need to change how I interpret the data I receive?

2 
      softwareSerial.print("Print Bytes = ");
      softwareSerial.println(bytes);

The println() function expects a NULL terminated array of chars. Your char array is NOT null terminated. Do NOT call println() to print it until AFTER you NULL terminate it.

3

I changed the code to null terminate the array of chars. I still get the same problem. It works fine when I use the hardware serial port but the same program doesn't work using the software serial through bluetooth. Even when I send a print bytes'', the char is not what it is supposed to be.
When I send a 'hello' it sees 'hY[­û'. Only the first char is right.
* *softwareSerial.listen();  long l = millis();  while (millis() - l < 1000) {    while (softwareSerial.available() > 0) {      readByte = softwareSerial.read();      bytes[i] = readByte;      softwareSerial.print(bytes[i]);      //delay(10);      if ( bytes[i] == eol ) {        bytes[i] = '\0';        i--;      }      i++;      readSomething = true;    }  }* *

4 
  softwareSerial.begin(115200);

That's usually way to fast for software serial Half that is pushing it.