ZB communication

XBee & XBee Gateway XBee - Zigbee
1

Hi,

I was trying to communicate several ZB modules between them. There was several routers and one coordinator, but I couldn’t, so instead I try to make a P2P communication.

I tried to used two modules in API mode (2, with escaped character), they associated right, but I don’t receive anything. I couldn’t find the problem.

After that, I tried the most simple example, with two modules in AT mode (transparent), one send, another receive, so I write down my codes because the coordinator, the one which receives the data, didn’t show it well. It only shows wrong data.

I don’t know what is going wrong with this, because if I use x-ctu’s terminal it works fine!!

Can someone help me??

SEND

char *str = {"HOLA"};

int statusLed = 13;
int errorLed = 13;

unsigned long start = millis();
//___________________________________________________________________________________________

void flashLed(int pin, int times, int wait) {

  for (int i = 0; i < times; i++) {
    digitalWrite(pin, HIGH);
    delay(wait);
    digitalWrite(pin, LOW);

    if (i + 1 < times) {
      delay(wait);
    }
  }
}
//___________________________________________________________________________________________

void setup() {
  pinMode(statusLed, OUTPUT);
  pinMode(errorLed, OUTPUT);

  Serial.begin(57600);
  Serial.println("
	... XBee - ZB ...
");

  flashLed(statusLed, 1, 500);
}
//___________________________________________________________________________________________

void loop() {   
//  Serial.flush();

  Serial.println(str);
  delay(2000);			//wait 2 seconds

  Serial.flush();
//  delay(5000);
}

RECEIVE

int statusLed = 13;
int errorLed = 13;
int dataLed = 13;

char *str;
//___________________________________________________________________________________________

void flashLed(int pin, int times, int wait) {

  for (int i = 0; i < times; i++) {
    digitalWrite(pin, HIGH);
    delay(wait);
    digitalWrite(pin, LOW);

    if (i + 1 < times) {
      delay(wait);
    }
  }
}
//___________________________________________________________________________________________

void setup() {
  pinMode(statusLed, OUTPUT);
  pinMode(errorLed, OUTPUT);
  pinMode(dataLed,  OUTPUT);
  
  Serial.begin(57600);
  Serial.println("
	... XBee - ZB ...
");

  flashLed(statusLed, 1, 500);
}
//___________________________________________________________________________________________

void loop() {
  int i=0;
  
  /*if*/while (Serial.available()) {	//If there is data in the Serial Line
//    int dataByte = Serial.read(); //save data into integer variable dataByte
    str[i] = Serial.read();
    i++;
    
    //Serial.print(dataByte,BYTE); //Print to screen the variable received
    flashLed(statusLed, 12, 1000);        
    Serial.print(i,DEC);
    Serial.print(". ");
    Serial.println(str);
  }
  
  Serial.flush();
//  delay(5000);
}
2

konnbannwa,

in the RECEIVE side.

char *str; ------ The memory is not obtained although only pointer is obtained.

void loop() {
int i=0; ------ “i” has 0 substituted eternally.

str[i] = Serial.read(); ------ Although the memory is not obtained, substitution is performed compulsorily.
3

Hi,

first of all, thanks for your reply.

But I can’t understand what you mean with ‘memory is not obtained’ and ‘substitution is performed compulsory’. How can I fix it?? (char str[20]:wink:

The fact is that, sender sends almost 30 messages while receiver only shows 3 or 4 character.

I don’t know why is this happening.

Regards.

4

konnnichiwa,

Yes, I think that str [20] is a good method.

void loop() {
int i=0;
i++;

In this, whenever i goes into loop, it will be initialized by 0, and it will increase to 1 after that.
If you would like to increase i whenever it goes into loop,

static int i;

It carries out.
However, since the size of str will be exceeded, before exceeding the size of str, the processing which returns the value of i to 0 is required.

flashLed(statusLed, 12, 1000);

It is the biggest problem.
If this processing is started, you cannot return for 24 seconds, but is it OK?

5

Hi,

thanks!!

First of all, ‘flashLed’ function was erased. It only was for checking behaviour.

I finally get how communicate both modules in AT mode, my network fails sometimes at receive way, I think is because the delay’s I’m using in the code and the ‘Serial.flush()’ instruction I used at the end of the ‘loop’ function.

But I have to deal with it and look for fixing it.

My receive code is next:

int pin = 13;
char str;
//___________________________________________________________________________________________

void setup() {
  pinMode(pin,  OUTPUT);

  Serial.begin(57600);
  Serial.println("
	... XBee - ZB ...
");
}
//___________________________________________________________________________________________

void loop() {
  digitalWrite(pin, HIGH);

  while (Serial.available() > 0) {	//If there is data in the Serial Line
    str = Serial.read(); //save data into integer variable dataByte
    Serial.print(str);   //Print to screen the variable received
  }
  Serial.println("_____________________________");

  Serial.flush();

  delay(500);
  digitalWrite(pin, LOW);
  delay(5000);
}

Instead of ‘char *str’, I’m using only a char, but I’m being able to read fine by the UART.

I’ll thank any tip you can tell me.

Regards.