UnaClocker
Active member
I'm using a Teensy 3, with the final TeensyDuino code, Arduino 1.0.3.. ADXL345 hooked up via i2c. I've tried this library:
http://code.google.com/p/adxl345driver/
When I run the test sketch in that library, nothing happens on the serial monitor. I don't even get the initial message. With or without the ADXL345 connected, same result.
So then I tried the sketch from this URL:
http://codeyoung.blogspot.com/2009/11/adxl345-accelerometer-breakout-board.html
It runs, which is better than the last one, but I get nothing but zero's returned. Which is the same thing I get when the ADXL345 isn't even connected to the T3..
I have 1k pull-up resistors from 3.3v to pins 18 and 19, I don't quite understand why it's not working at this point.
http://code.google.com/p/adxl345driver/
When I run the test sketch in that library, nothing happens on the serial monitor. I don't even get the initial message. With or without the ADXL345 connected, same result.
So then I tried the sketch from this URL:
http://codeyoung.blogspot.com/2009/11/adxl345-accelerometer-breakout-board.html
Code:
//ADXL345 code from http://codeyoung.blogspot.com/2009/11/adxl345-accelerometer-breakout-board.html
#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
void setup()
{
Wire.begin(); // join i2c bus (address optional for master)
Serial.begin(57600); // start serial for 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);
sprintf(str, "%d", z);
Serial.print(str);
Serial.print(10, BYTE);
//It appears that delay is needed in order not to clog the port
delay(15);
}
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
}
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 (initiate again)
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
}I have 1k pull-up resistors from 3.3v to pins 18 and 19, I don't quite understand why it's not working at this point.
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