@Steven_Turner please connect Serial I2C connector through the breakout board and ensure that CAN is not connected. I2C line is how Here4 detects that it needs to be in Serial I2C mode and will receive LED commands over it. So if successfully detected, you should see Ardupilot LEDs working.
On Ardupilot, you will need to set GPS_DRV_OPTION bitmask for 115200 as well. This feature is not very well tested, so please feedback how it goes.
I am in a similar situation and have not been successful in getting it to work.
I got the I2C working, or at least It appears to be, the red status lights are flashing. Before I2C was working they were simply white. I tried changing GPS_DRV_OPTION as instructed above, I don’t have that option so think I worked around it by changing the GPS Serial Baud rate to the 115200 mentioned above. I’ve double checked that its pinned out correctly and have even tried it both ways.
I have pushed some fixes to enable Serial I2C operation. Following parameters need setting on Ardupilot:
GPS_DRV_OPTIONS 4 # Enables Ublox to operate at 115200
GPS_TYPE/GPS_TYPE2 2 # Defines GPS Type to be Ublox, this is needed to honour above option
GPS_SAVE_CFG 1 # Ensures that baudrate 115200 sticks
Also I2C line needs to be connected as well, and CAN disconnected. I2C is how Here4 will know that it needs to switch to Serial/I2C operation. No other config on Here4 is needed. You should also see status LEDs behaving per Ardupilot status, and also RM3100 mag should appear as well.
Thanks for the update Siddharth, my Adrupilot bench test seems to be working, haven’t flown it. The copter I need to fly I2C uses PX4/QGC and doesn’t have the same options. Are there a set of parameters I can change there to achieve the same results?
@palma For getting serial/i2c operation to work. Please use the steps as I mentioned in above comments and also set the parameters as needed.
Although the compass issue seems to be a separate issue, have you enable CAN and followed the process here to do so? DroneCAN Setup — Copter documentation Do you then see DroneCAN GPS show up in the compass setup page of mission planner? Please raise a separate issue for this on the forum, we can continue this part of discussion there.