Request message from ardupilot

ArduCopter
1

Hi,
I send (from companion raspberry pi board) to mRo pixhawk requests for position message(#33) using COMMAND_LONG ([ #76 ] with MAV_CMD_REQUEST_MESSAGE ([512] parameter.
I send the requests at 50 Hz (also 40 Hz, 20 Hz…) but the response is not at the appropriate rate.
Why? Are there any limitations to ardupilot software? the pixhawk hardware?

2

Try

   <entry value="511" name="MAV_CMD_SET_MESSAGE_INTERVAL"

hasLocation=“false” isDestination=“false”>

Instead :slight_smile:

3

Thanks Peter,
I’ve tried entry value=“511” name=“MAV_CMD_SET_MESSAGE_INTERVAL” as well.
Unfortunately , The rate of response for the requested message, is not steady and correct.
I ask for interval of 20, 40, 50 ms.

4

What rate are you getting?

If you try raising an entire streamrate rather than an individual message
(reboot may be required…) - does that behave itself?

5

I’m trying to get individual message (position #33 , attitude # 30) , not entire stream.
anyway, the responses are sometimes in bursts and sometimes the interval between successive messages is much bigger than the requested interval. the responses do not arrive in a steady rate.

6

Do they arrive at a steady rate before you request them at a different
rate?

7

I’m not sure. I’ll check it.