Go Down

Topic: HMC6352 not accurate (Read 1 time) previous topic - next topic


Hello everyone,

I have been battling with the programing of the compass HMC6352 to get accurate reading but so far all what I have done has not work...
Well I am using arduino UNO atmega328P. see below the code I used.
while I upload the code, I have readings but the problem comes when I rotate the compass 90degrees. the resulting indication on the serial monitor does not reflect the same 90degrees. I would like to calibrate and I wrote the code for calibration with which I tested the compass once more. but no change.

can anyone lead me or provide me with the calibration code... or anything that will help me move forward...

thank you

#include <Wire.h>
#include <LiquidCrystal.h>

//LiquidCrystal lcd(12, 11, 5, 4, 3, 2);       // initialize the numbers of the interface pins

int compass_address = 0x42;                  // initialization of the address of the compass
int slave_address, i, current_value, heading_value; // declaration of variables
byte heading_data[2];                        // declaration of heading_data as array

void setup()

slave_address = compass_address >> 1;        // this shift the bit right one position results in 0x21 as the address to pass to TWI
Serial.begin(9600);   // determine the speed of data transmission
// set up
 CLKPR = 0;
// lcd.begin(16, 4);                           // set the LCD's number of columns and rows
// lcd.setCursor(0, 0);                        // set the cursor to column 0 and line 1
// lcd.print("Robot heading");                 // Print a message to the LCD

void loop()
 Wire.beginTransmission(slave_address);     // start of data transmission
 Wire.send("A");                            // get current data
 Wire.endTransmission();                    // end of data transmission
 delay(100);                               // delay of 1s before refreshing the data

 Wire.requestFrom(slave_address, 2);        // request the 2 bytes heading of 8 bits each
 i = 0;
 while(Wire.available() && i < 2)
   heading_data = Wire.receive();
 heading_value = (heading_data[0]*256 + heading_data[1]);  // add the first byte (MSB) and second byte (LSB)

 current_value = heading_value/10;
//  lcd.setCursor(0, 1);
 Serial.print(heading_value %10);
// Serial.setCursor(7, 1);
 delay(100);                // only 70 microseconds are necessary


What's up with the poll? I wanted to vote s (for stupid) but that's not a choice.

Go Up

Please enter a valid email to subscribe

Confirm your email address

We need to confirm your email address.
To complete the subscription, please click the link in the email we just sent you.

Thank you for subscribing!

via Egeo 16
Torino, 10131