Connecting extra Servo to ArdupilotMega

Other Hardware Motors, Mechanics, Power and CNC
1

  1. Looking at schematic for APM (w/ ATmega 2560) I think what's labelled as "OUT5" on the APM Board is Arduino Pin 8. True?

  2. I hook up a servo to OUT5. Then in only one place I change the follow bundled sketch. I change from attaching pin 9 to attaching pin 8. The servo works on another board, noprob. Why doesn't this work?

// Sweep
// by BARRAGAN http://barraganstudio.com
// This example code is in the public domain.

#include <Servo.h>

Servo myservo; // create servo object to control a servo
// a maximum of eight servo objects can be created

int pos = 0; // variable to store the servo position

void setup()
{
myservo.attach(9); // attaches the servo on pin 9 to the servo object
}

void loop()
{
for(pos = 0; pos < 180; pos += 1) // goes from 0 degrees to 180 degrees
{ // in steps of 1 degree
myservo.write(pos); // tell servo to go to position in variable 'pos'
delay(15); // waits 15ms for the servo to reach the position
}
for(pos = 180; pos>=1; pos-=1) // goes from 180 degrees to 0 degrees
{
myservo.write(pos); // tell servo to go to position in variable 'pos'
delay(15); // waits 15ms for the servo to reach the position
}
}

2

Answering my questions -

1 Yes. What's labeled "OUT5" on the APM (2560) board is Pin 8.

I got servo to work using signal from OUT5 using sketch changing only output pin to pin 8.

  1. I guess it wasn't working because there wasn't enough power.

When I use power from some other source than the two pins next to the signal pin it works. I don't exactly know why there wasn't enough coming from there since those pins are similarly configured to other pins and nominally you are supposed to be able to hook a camera up there.