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[melball]

Hi,

I'm using this library for the ADXL345: http://bildr.org/2011/03/adxl345-arduino/

My code is quite simple. The bluetooth part of this gives no trouble, if I replace it by flashing lights I get the exact same problem. After a few minutes (about 3), sometimes less, the free fall stops giving off any interrupts (also not any tap interrupts if I add those to the code, or xyz info) and the only way to get it to work again is a restart. I've tested if it's alive when this happens (yes), asleep (no), in low power mode(no). If I recreate this with only tap instead of free fall I seem to have no problems so it seems free fall specific that it gets blocked. Does anyone have a clue what's happening here?

Code: Select all

#include <ADXL345.h>
#include <Wire.h>
#include <SoftwareSerial.h>

const byte PIN_BLUETOOTH_RX = 2;
const byte PIN_BLUETOOTH_TX = 5;
SoftwareSerial* bluetooth;
ADXL345 adxl;

void setup(){
  
  bluetooth = new SoftwareSerial(PIN_BLUETOOTH_RX, PIN_BLUETOOTH_TX);
  bluetooth->begin(9600);
  adxl.powerOn();
  
  //The FREE_FALL bit is set when acceleration of less than the value stored in the THRESH_FF register (Address 0x28)
  // is experienced for more time than is specified in the TIME_FF register (Address 0x29) on all axes (logical AND).
  adxl.setFreeFallThreshold(9); //(5 - 9) recommended - 62.5mg per increment
  adxl.setFreeFallDuration(20); //(20 - 70) recommended - 5ms per increment
  
  adxl.setInterruptMapping(ADXL345_INT_FREE_FALL_BIT,    ADXL345_INT1_PIN);
 
  //register interupt actions - 1 == on; 0 == off  
  adxl.setInterrupt(ADXL345_INT_FREE_FALL_BIT,  1);
  
}

void loop(){
  
  byte interrupts = adxl.getInterruptSource();    

    if(adxl.triggered(interrupts, ADXL345_FREE_FALL))
    {
      sendBluetoothMessage(6, 1);
    }

}


void sendBluetoothMessage(byte messageType, int message){

  for(int i = 0; i< 11; i++){
    bluetooth->write(byte(0));
  }

  bluetooth->write(messageType);

  byte b[4];
  IntegerToBytes(message, b);
  for (int i = 0; i < 4; i++) {
      bluetooth->write(b[i]);
  }

}

void IntegerToBytes(long val, byte b[4]) {
  b[0] = (byte )((val >> 24) & 0xff);
  b[1] = (byte )((val >> 16) & 0xff);
  b[2] = (byte )((val >> 8) & 0xff);
  b[3] = (byte )(val & 0xff);
}