switch pins after a time period

Projects General Guidance
1

Hi guys, I am a complete N00B here, and im pretty much making this up as I go along for a design project.

I have a working ADXL345 code which activates pin 13 on when the accelerometer moves, however I need to add a feature so after say 1 min pin 13 turns off and pin 12 activates.

any ideas?

cheers

#include <Wire.h>

#define DEVICE (0x53)    //ADXL345 device address
#define TO_READ (6)        //num of bytes we are going to read each time (two bytes for each axis)

byte buff[TO_READ] ;    //6 bytes buffer for saving data read from the device
char str[512];                      //string buffer to transform data before sending it to the serial port
const int ledPin=13;
void setup()
{
  Wire.begin();        // join i2c bus (address optional for master)
  Serial.begin(9600);  // start serial for output
  pinMode(ledPin,OUTPUT);
  //Turning on the ADXL345
  writeTo(DEVICE, 0x2D, 0);      
  writeTo(DEVICE, 0x2D, 16);
  writeTo(DEVICE, 0x2D, 8);
}

void loop()
{
  int regAddress = 0x32;    //first axis-acceleration-data register on the ADXL345
  int x, y, z;
  
  readFrom(DEVICE, regAddress, TO_READ, buff); //read the acceleration data from the ADXL345
  
   //each axis reading comes in 10 bit resolution, ie 2 bytes.  Least Significat Byte first!!
   //thus we are converting both bytes in to one int
  x = (((int)buff[1]) << 8) | buff[0];   
  y = (((int)buff[3])<< 8) | buff[2];
  z = (((int)buff[5]) << 8) | buff[4];
  
  //we send the x y z values as a string to the serial port
  sprintf(str, "%d %d %d", x, y, z);
if (x<-5) {  sprintf(str,"%d %s",x,"Limit -x");digitalWrite(ledPin,1); }
if (x>15) {  sprintf(str,"%d %s",x,"Limit              x");digitalWrite(ledPin,1);}
if (y<0) {  sprintf(str,"%d %s",y,"Limit -y"); digitalWrite(ledPin,1);}
if (y>30) {  sprintf(str,"%d %s",y,"Limit              y"); digitalWrite(ledPin,1);}
if (z<220) {  sprintf(str,"%d %s",z,"Limit -z"); digitalWrite(ledPin,1);}
if (z>250) {  sprintf(str,"%d %s",z,"Limit              z"); digitalWrite(ledPin,1);}
  Serial.print(str);
  Serial.print(10, BYTE);
  
  //It appears that delay is needed in order not to clog the port
  delay(15);
}

//---------------- Functions
//Writes val to address register on device
void writeTo(int device, byte address, byte val) {
   Wire.beginTransmission(device); //start transmission to device 
   Wire.send(address);        // send register address
   Wire.send(val);        // send value to write
   Wire.endTransmission(); //end transmission
}

//reads num bytes starting from address register on device in to buff array
void readFrom(int device, byte address, int num, byte buff[]) {
  Wire.beginTransmission(device); //start transmission to device 
  Wire.send(address);        //sends address to read from
  Wire.endTransmission(); //end transmission
  
  Wire.beginTransmission(device); //start transmission to device
  Wire.requestFrom(device, num);    // request 6 bytes from device
  
  int i = 0;
  while(Wire.available())    //device may send less than requested (abnormal)
  { 
    buff[i] = Wire.receive(); // receive a byte
    i++;
  }
  
  
  Wire.endTransmission(); //end transmission
}

Moderator edit: Code in code box, instead of quote box with smilies

2

Make a note of the time when you wrote the pin HIGH (using "millis()"),then one minute later write the pin LOW.
Have a look at the blink without delay example for further clues.