Hi,
I bought a Twig accelerometer, gyro and compass. None of them seem to respond. I’ve connected them up to Vcc/GND/A4/A5 on my Arduino Diecimila and to the I2C ports on my Seeeduino Mega. I am using the compass reading code provided on the Seeedstudio Wiki. It says this no matter what orientation the sensor is in: “You are heading NorthEast: Angle between X-axis and the South direction 135.0000000000 Deg”.
I also used the following code to scan the I2C bus, and the devices do not show up:
#include "Wire.h"
extern "C" {
#include "utility/twi.h" // from Wire library, so we can do bus scanning
}
// Scan the I2C bus between addresses from_addr and to_addr.
// On each address, call the callback function with the address and result.
// If result==0, address was found, otherwise, address wasn't found
// (can use result to potentially get other status on the I2C bus, see twi.c)
// Assumes Wire.begin() has already been called
void scanI2CBus(byte from_addr, byte to_addr,
void(*callback)(byte address, byte result) )
{
byte rc;
byte data = 0; // not used, just an address to feed to twi_writeTo()
for( byte addr = from_addr; addr <= to_addr; addr++ ) {
rc = twi_writeTo(addr, &data, 0, 1);
callback( addr, rc );
}
}
// Called when address is found in scanI2CBus()
// Feel free to change this as needed
// (like adding I2C comm code to figure out what kind of I2C device is there)
void scanFunc( byte addr, byte result ) {
Serial.print("addr: ");
Serial.print(addr,DEC);
Serial.print( (result==0) ? " found!":" ");
Serial.print( (addr%4) ? "\t":"\n");
}
byte start_address = 1;
byte end_address = 119;
// standard Arduino setup()
void setup()
{
Wire.begin();
Serial.begin(19200);
Serial.println("\nI2CScanner ready!");
Serial.print("starting scanning of I2C bus from ");
Serial.print(start_address,DEC);
Serial.print(" to ");
Serial.print(end_address,DEC);
Serial.println("...");
// start the scan, will call "scanFunc()" on result from each address
scanI2CBus( start_address, end_address, scanFunc );
Serial.println("\ndone");
}I have tried doing this with and without pull-up resistors. What is going wrong? It seems like the sensors just don’t work.