Program pixhawk with servo motor

Hi there.
I am here trying to make a agriculture use drone using pixhawk
I have some dispenser system which is connected with servo motor
I need to program pixhawk to operate servo automatically when it reaches to waypoint
I am planning to drop seed at perticular location by using servo moto so can anyone help to guide me

sure, there is a DO_SET_SERVO command that you can put into missions.

So do i need to use lua script or i can directly program it?

Command which @amilcarlucas mentioned can be directly use to control servos for missions in auto mode

Thanks for help guys
Here I am using 6 channel tx rx and I am using hexacopter
I have connected it by ppm output
Now i need to add servo into pixhawk and automate it in mission planner as mentioned above
So can i do it with 6 channel if i neeed to automate that thing
And can you help me that how can I be able to add servo to the pixhawk for that kind of condition

Thank you

Connect the servo to CH9 output. And configure it.

Here i am using 6 channel transmitter and receiver

That is the point, it can and should be connected to a output channel controlled by ArduCopter missions.
Not to a channel controlled by the RC transmitter, hence no ppm involved at all.

Ok i understand but in pixhawk 2.4.8 i can find that thare is 8 main out and 6 aux out
So can you please tell me that where can i find CH9 and how to configure it

OUT 9 is AUX1
Take a look at the SERVO9_FUNCTION parameter.
And RC9_OPT

The documentation to do what you want is https://ardupilot.org/copter/docs/common-servo.html#controlling-the-servo-as-a-servo

Thanks for your help