Comments on: HMC5843 Magnetometer Library for Arduino

By: FukKuen

FukKuen — Thu, 06 Oct 2011 22:19:53 +0000

I have brought the sensors 2 month ago but still not yet get the correct readings…
After I have read the comments I have brought a capacitor (100uF, 16V), but i dont know how to connect that to the circuit (in parallel). could anybody describe it in detail or show me a photo?

By: Anonymous

Anonymous — Sat, 16 Jul 2011 21:51:07 +0000

I need the same how can I get an angel?

By: ali

ali — Fri, 15 Jul 2011 19:39:58 +0000

hello
i bought hmc5843 and i could get data from it but i dont know how i can change these data to gauss and the most important i dont know how i can change the output to the angels

By: Nintendo DS Touch Screen and breakout board | inmotion.pt

Nintendo DS Touch Screen and breakout board | inmotion.pt — Tue, 21 Jun 2011 23:29:13 +0000

[...] on-board regulator, so a regulated voltage of 2.5-3.3VDC should be supplied. Check out this Arduino library and this tutorial on verifying the accuracy of its [...]

By: Luís Mauro

Luís Mauro — Thu, 06 Jan 2011 20:40:20 +0000

Hello

I´m having another BAD experience with a DIYdrones board.

If it´s possible, please take a look at this forum:
http://diydrones.com/forum/topics/hmc5843-3-axis-magnetometer?commentId=705844:Comment:248254

If you have any idea about what is going wrong, I appreciate very much!!

Thank you

Luís

By: Frank

Frank — Thu, 06 Jan 2011 03:11:22 +0000

I tried just using Wire library on HMC5883L. It works fine. So I believe that Wire library should also works fine for HMC5843. HMC5843 and HMC5883L are very similar.
please see the complete code below:

#include
void setup()
{
initHMC5883L();
}
void loop()
{
readxyz();
}
void initHMC5883L()
{
Wire.beginTransmission(0x1E);// 7 bits address //0x3C //datasheet page 17
Wire.send(0×02);
Wire.send(0×00); // continues reading
Wire.endTransmission();
}

void readxyz()
{
Wire.beginTransmission(0x1E);
Wire.send(0×03);
Wire.endTransmission();

Wire.requestFrom(0x1E, 6);
if(6 <= Wire.available())
{
int x,y,z;
x = Wire.receive() << 8;
x |= Wire.receive();
y = Wire.receive() << 8;
y |= Wire.receive();
z = Wire.receive() << 8;
z |= Wire.receive();
}
}

By: austiey

austiey — Thu, 09 Dec 2010 18:44:14 +0000

I’m having the same problem. Martin: Have you figured out a solution yet?

By: Fabio Varesano

Fabio Varesano — Wed, 01 Dec 2010 12:31:15 +0000

I just completed porting the HMC5843 Arduino library, originally created by Nirav Patel (see above) and then extended/improved by E.J.Muller (http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1274748346/0#0), to use only the Arduino Wire library to use the I2C bus.

If this interests you, you’ll find it at http://www.varesano.net/blog/fabio/hmc5843-magnetometer-library-arduino-based-wire

By: nrp

nrp — Sun, 14 Nov 2010 06:00:56 +0000

Those values are a possible symptom of the capacitor issue, but could be something else. I recommend trying the capacitor fix if at all possible.

By: Martin

Martin — Sat, 13 Nov 2010 21:35:21 +0000

Hi,
sorry to bother you with my ignorance, but I keep failing with reading the HMC5843.
the sketch (the one on top of this page, with the hmc.h lib) is compiling and running without errors, but constantly delivers all the same value:

x:15677 y:15677 z:15677
x:15677 y:15677 z:15677
x:15677 y:15677 z:15677

I am an absolute noob in i2c (actually, in Arduino stuff as well), and have no idea on how I can track down the problem.
wiring is ok I guess (Arduino Uno, getting the 3.3V from board, Data pin on A4, clock on A5).

as the hex value of 15677 is 3D3D, I have the suspicion that the sent data is somehow taken as read data (because the read address of the HMC is 3D as well… just a clueless wild guess…).
I did not try the capacitor fix because I do not want to fry anything, but I think it is a general i2c communication issue that I am facing.

most grateful for any hint,
martin