Hey guys new to the arduino scene and having some possible newb issues. I have a trinket from adafruit and no matter what I try I can't get a servo to do a simple sweep, I've tried the arduino sweep code to no avail. Am I missing something super basic with that code I've added the servi libraries etc.. Thanks in advance
The trinket is an ATtiny85 board and doesn't work with all the various Arduino libraries. The good news is Adafruit has excellent tutorials. Check this out Overview | Trinket (& Gemma) Servo Control | Adafruit Learning System
You need to spend some time on the Adafruit website and go through the tutorials there to get a good start. You have one foot in the door of the Arduino scene, come all the way in by getting an Uno, Pro Mini with matching FTDI basic, or Nano next.
I was able to control the servo via the potentiometer but I'm struggling to get the servo to sweep automatically without the potentiometer
Well, in the Adafruit tutorial where you control the servo with the pot,
Arduino Code | Trinket (& Gemma) Servo Control | Adafruit Learning System,
the desired servo position comes from reading the pot:
potValue=analogRead(POTPIN);
and then that number between 0 and 1023 is changed to a number between 0 and 179 which the servo needs, with the statement:
servoPos = map(potValue, 0, 1023, 0, 179);
Here is the whole loop
void loop() {
int potValue; // variable to read potentiometer
int servoPos; // variable to convert voltage on pot to servo position
potValue=analogRead(POTPIN); // Read voltage on potentiometer
servoPos = map(potValue, 0, 1023, 0, 179); // scale it to use it with the servo (value between 0 and 180)
myServo1.write(servoPos); // tell servo to go to position
delay(15); // waits 15ms for the servo to reach the position
}
So if you replace those lines with some code that increments the desired servo value from 0 to 179 it will sweep the servo. When I look at the Arduino IDE servo sweep example, I notice some code that could be borrowed and inserted in the Adafruit pot/servo example, just changing the variable names. Try something like this (note I did not test this, I don't have a servo and ATtiny85 board handy at the moment):
void loop() {
int servoPos; // variable to convert voltage on pot to servo position
for(servoPos = 0; servoPos <= 180; servoPos += 1) // goes from 0 degrees to 180 degrees
{ // in steps of 1 degree
myServo1.write(servoPos); // tell servo to go to position in variable 'pos'
delay(15); // waits 15ms for the servo to reach the position
}
for(servoPos = 180; servoPos >=0; servoPos-=1) // goes from 180 degrees to 0 degrees
{
myServo1.write(servoPos); // tell servo to go to position in variable 'pos'
delay(15); // waits 15ms for the servo to reach the position
}
delay(1000); // waits a second, then go through the loop again
}