AP_periph PWM ESC configuration issue

ArduPlane Plane 4.6
,
1

I am having issues with PWM ESCs on the Matek L431-PWM node.

Note that this is a PLANE with “throttle left” and “throttle right”. If it were a multirotor or qudplane the outputs would be ESC1, ESC2 etc. But this does not seem to be the case for a trad plane?

PWM servos work fine - I can map servo 1 in mission planner to 51 on the can node…perfect!

The difficulty comes with the PWM Esc.

Assuming throttle left is allocated to servo 2 in mission planner, I can assign an output on the node to “52”.
The default trim within the node is set to1500 and the trim set in mission planner is being ignored. This means that on boot the ESC gives an error because throttle is not zero. I can fix this by changing the trim on the node to 1100. The ESC then arms but it only spins when the throttle stick is above 50%. To fix that I have to put the trim value back to 1500 on the node.

So current preflight process is to connect to the node, put trim to 1100 to arm the ESC and then put the trim back to 1500 so I can fly. This does not seem correct behaviour to me.

Am I missing something? Should the ESC be mapped as a 33+ number? if so what number is throttle left and throttle right?

3

This thread can be deleted.

the issue was that the throttle left and right are indeed mapped as escs. Using the can_d1 esc bitmask.

The cause of the confusion was that the servos are indexed from 1.

the escs are indexed from 0.

4

No need to delete, somebody will struggle with that in the future. It probably should be noted in the documentation.

PS I changed the tittle of the thread to make it more generic and easier to find it somebody runs into the issue.

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