fio.md

#Arduino Fio with Accel/Gyro combo

The Fio uses analog pins 4 and 5 for I2C. A4 is SDA and A5 is SCL.

3.3V and GND come from their respective pins on the Fio.

Communicating over the XBee is just done with the normal serial library.

An example Arduino sketch to read the device IDs and send them out over XBee:

#include <Wire.h>

#define accel_addr  (0x53)
#define gyro_addr   (0x68)

void setup() {
    Serial.begin(57600);
    Wire.begin();
}

char get_accel_devid()
{
    char devid;
    readFromAccelAddr(0x00, 1, &devid);
    return devid;
}

char get_gyro_devid()
{
    char devid;
    readFromGyroAddr(0x00, 1, &devid);
    return devid;
}

char readFromAccelAddr(char addr, char num, char* buff) 
{
    Wire.beginTransmission(accel_addr);
    Wire.write(addr);
    Wire.endTransmission();
    Wire.beginTransmission(accel_addr);
    Wire.requestFrom(accel_addr, 1); 
    int i;
    for (i = 0; i < num; i++) {
        while(!Wire.available()); // wait for recv
        buff[i++] = Wire.read();
    }
    Wire.endTransmission();
}

char readFromGyroAddr(char addr, char num, char* buff) 
{
    Wire.beginTransmission(gyro_addr);
    Wire.write(addr);
    Wire.endTransmission();
    Wire.beginTransmission(gyro_addr);
    Wire.requestFrom(gyro_addr, 1); 
    int i;
    for (i = 0; i < num; i++) {
        while(!Wire.available()); // wait for recv
        buff[i++] = Wire.read();
    }
    Wire.endTransmission();
}

void loop() {
    Serial.write(get_accel_devid());
    Serial.println("");
    Serial.write(get_gyro_devid());
    Serial.println("");
    delay(500);
}