Servo Motors are one of the most important actuators in the realm of robotics being applied in use cases from RC planes to automated door locks. Therefore, this second module of the ESP32 lesson, we will cover how to control servo motors.
Interfacing a servo motor to the ESP32 is very difficult compared to an Arduino, since it does not support analogWrite(). However, it uses various frequencies and timers, allowing the all digital pins to be used as PWM pins as well send signals significantly faster than any Arduino!!!
#define COUNT_LOW 0
#define COUNT_HIGH 8888
#define TIMER_WIDTH 16
#include "esp32-hal-ledc.h"
void setup() { ledcSetup(1, 50, TIMER_WIDTH); // channel 1, 50 Hz, 16-bit width ledcAttachPin(2, 1); // GPIO 22 assigned to channel 1 }
void loop() { for (int i=COUNT_LOW ; i < COUNT_HIGH ; i=i+100) { ledcWrite(1, i); // sweep servo 1 delay(50); } }
The servo motions follows as programmed going from the minimum to maximum at much faster speeds relative to an Arduino or ESP8266.