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[on:]

I don't know how many people have actually done this, but my day was spent getting this to work.
So to start with, you need to cut a lego cable
Soldering/tinning the ends works best

Then, with a breadboard most likely, connect the pins 1 and 4 to 5v, 2 and 3 to ground, 5 and 6 to I2C clock and data respectively.
Then the code:

Code:

#include "Wire.h"
void setup()
{
  Wire.begin();
  Serial.begin(19200);           // start serial for output
}

void loop()
{
  Wire.beginTransmission(1); // transmit to device #1(lego accelerometer
  Wire.send(0x42);           // sends Read first 8 bits of accelerometer
  Wire.endTransmission();
  delay(700);
  Wire.requestFrom(1, 8);
  while(Wire.available())
  {
    char c = Wire.receive();
    Serial.println(c,HEX);    //output the data
  }
  Serial.print("Done \n");
  delay(500);
}

Fairly simple, but I had trouble googling it, so I did it myself
The rest of the request bytes can be found on the hitechnic site

Always glad to help
~Nai

[Reply #1 on:]

You might have to take a look at the datasheet on the accelerometer, for the I2C connection. Are you receiving any type of data back? If so, will you post it.

[Reply #2 on:]

Nope, got it working. One of the wires was broken inside the connector.
Also, for anyone else doing this here's the code:

Code:

#include "Wire.h"
void setup()
{
  Wire.begin();
  Serial.begin(19200);
}

void loop()
{
  Wire.beginTransmission(1);
  Wire.send(0x42);
  Wire.endTransmission();
  delay(20);
  Wire.requestFrom(1, 1);
  char b;
  while(Wire.available())
  {
    b = Wire.receive();
  }
  delay(50);
  Wire.send(0x45);  
  Wire.endTransmission();
  delay(20);
  Wire.requestFrom(1, 1);
  while(Wire.available())
  {
    char c = Wire.receive();
    int i = (c & 3) + (b << 2);
    Serial.println(i,DEC);
  }
  delay(500);
}