67 lines
3.1 KiB
C++
67 lines
3.1 KiB
C++
/* Sweep
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by BARRAGAN <http://barraganstudio.com>
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This example code is in the public domain.
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modified 8 Nov 2013
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by Scott Fitzgerald
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modified for the ESP32 on March 2017
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by John Bennett
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see http://www.arduino.cc/en/Tutorial/Sweep for a description of the original code
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* Different servos require different pulse widths to vary servo angle, but the range is
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* an approximately 500-2500 microsecond pulse every 20ms (50Hz). In general, hobbyist servos
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* sweep 180 degrees, so the lowest number in the published range for a particular servo
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* represents an angle of 0 degrees, the middle of the range represents 90 degrees, and the top
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* of the range represents 180 degrees. So for example, if the range is 1000us to 2000us,
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* 1000us would equal an angle of 0, 1500us would equal 90 degrees, and 2000us would equal 1800
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* degrees.
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*
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* Circuit: (using an ESP32 Thing from Sparkfun)
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* Servo motors have three wires: power, ground, and signal. The power wire is typically red,
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* the ground wire is typically black or brown, and the signal wire is typically yellow,
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* orange or white. Since the ESP32 can supply limited current at only 3.3V, and servos draw
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* considerable power, we will connect servo power to the VBat pin of the ESP32 (located
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* near the USB connector). THIS IS ONLY APPROPRIATE FOR SMALL SERVOS.
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*
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* We could also connect servo power to a separate external
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* power source (as long as we connect all of the grounds (ESP32, servo, and external power).
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* In this example, we just connect ESP32 ground to servo ground. The servo signal pins
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* connect to any available GPIO pins on the ESP32 (in this example, we use pin 18.
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*
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* In this example, we assume a Tower Pro MG995 large servo connected to an external power source.
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* The published min and max for this servo is 1000 and 2000, respectively, so the defaults are fine.
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* These values actually drive the servos a little past 0 and 180, so
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* if you are particular, adjust the min and max values to match your needs.
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*/
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#include <ESP32Servo.h>
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Servo myservo; // create servo object to control a servo
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// 16 servo objects can be created on the ESP32
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int pos = 0; // variable to store the servo position
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// Recommended PWM GPIO pins on the ESP32 include 2,4,12-19,21-23,25-27,32-33
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int servoPin = 18;
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void setup() {
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myservo.attach(servoPin); // attaches the servo on pin 18 to the servo object
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// using default min/max of 1000us and 2000us
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// different servos may require different min/max settings
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// for an accurate 0 to 180 sweep
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}
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void loop() {
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for (pos = 0; pos <= 180; pos += 1) { // goes from 0 degrees to 180 degrees
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// in steps of 1 degree
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myservo.write(pos); // tell servo to go to position in variable 'pos'
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delay(15); // waits 15ms for the servo to reach the position
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}
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for (pos = 180; pos >= 0; pos -= 1) { // goes from 180 degrees to 0 degrees
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myservo.write(pos); // tell servo to go to position in variable 'pos'
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delay(15); // waits 15ms for the servo to reach the position
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}
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}
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