Reading Compass CMPS03

[Jawahar]

I am trying to read PWM signal from CMPS03 digital compass. The PWM signal is connected to TC0 pin of IsoPod V2. I have used the code available on your website.

But all I get is "0 519 deg". It does not change even if I rotate the compass. The connections have been verified. Why am I not getting the readings?

Thanks.

[Dave]

Have you calibrated the Devantech Compass according to their documentation at
http://www.robot-electronics.co.uk/htm/cmps3doc.shtml

Once calibrated at each of the 4 directions, it should read correctly from the IsoPod program.

[Jawahar]

I am getting readings now!

Actually, I mistook TA0 as TC0. After connecting the Compass PWM to TA0 as required by the code, I am getting readings.

But like you said, I still need to calibrate to get better measurements.

Thanks!

[Junjie87]

Hi, i'm using the compass CMPS03 with the microprocessor PIC16F84. I have problems with getting accurate results.
I'm using register 1 to obtain my results. At a same location, i get different values, but sometimes the values are quite far apart, as in one moment it reads '358', another moment it reads '80'.
Any advice anyone?

[Dave]

Yes, my advice would be to use one of our Pods to read the compass, and follow the example code on the Pods Download page. (http://www.newmicros.com/store/product_details/download.html)