Honeywell HMC5843 via I2C to PIC4550

trauma · Joined: 27 Nov 2008 Posts: 2

Hi,

we got problems connecting the HMC5843 Magnetometer to the PIC.
It seems to have data ready (Testpoint Pin19 is high), but it does not acknowledge the i2c_write(0x3D).

The only reason I can think of, is that the HMC5843 does not handle the 3.3V on the i2c lines, which is not clear from the datasheets.

One weird behavior is that the PIC pulls up the lines by itself (apparently no pull-up resistors needed for SCL and SDA).

Any ideas?
Thanks,
Ulf

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

You need to post your driver routines and a test program.

See the following post for an example of a test program for an
HMC compass product.
http://www.ccsinfo.com/forum/viewtopic.php?t=35914

Your posted code should be about the same length, and in the
same style. It should be compilable without errors.