Got it working today. Only thing that's wrong is that I have slightly erratic behavior from the sensor.
If I upload the HMC5833L code, there's no erratic behavior. It is inly when transmitting.
Can anyone see anything in the previous code that would cause this? This is both on Tx and Rx side, tested on Serial Monitor so I'm pretty sure the fault would be in the transimitter code.
I get data every 1000ms or so:
Heading: 271.99 st.
Heading: 358.37 st.
Heading: 358.37 st.
Heading: 358.37 st.
Heading: 272.01 st.
Heading: 271.99 st.
Heading: 271.99 st.
Heading: 271.56 st.
Heading: 271.99 st.
Heading: 271.54 st.
Heading: 271.56 st.
Heading: 6.32 st.
Heading: 271.54 st.
Heading: 271.99 st.
Heading: 271.56 st.
Heading: 271.56 st.
Heading: 358.37 st.
Heading: 271.54 st.
Heading: 272.01 st.
Heading: 271.99 st.
Heading: 272.01 st.
Heading: 272.46 st.
Heading: 272.01 st.
Heading: 272.01 st.
Heading: 87.53 st.
Heading: 272.02 st.
Heading: 271.99 st.
Heading: 271.99 st.
Heading: 272.01 st.
Heading: 358.37 st.
Heading: 271.99 st.
Heading: 272.01 st.
Heading: 271.99 st.
Oh and no, I'm not moving the magnetometer 