Hello,
I'm trying to use a servo with an esp32.
I'm using a uPesy ESP32 Wroom Devkit v2
The servo is TS90D digital 180°
I actually made it work. Two days later is wasn't working anymore. I tried with different ESP32, USB cables, servo and libraries... I can't figure out what's wrong, but I'm pretty sure it's dumb.
The potentiometer seems to works, seem I've got reading.
// Include the ESP32 Arduino Servo Library instead of the original Arduino Servo Library
#include <ESP32Servo.h>
Servo myservo; // create servo object to control a servo
int servoPin = 26; // GPIO pin used to connect the servo control (digital out)
int potPin = 27;
int ADC_Max = 4096; // This is the default ADC max value on the ESP32 (12 bit ADC width);
// this width can be set (in low-level oode) from 9-12 bits, for a
// a range of max values of 512-4096
int val; // variable to read the value from the analog pin
void setup()
{
Serial.begin(9600);
myservo.attach(servoPin);
}
void loop() {
val = analogRead(potPin); // read the value of the potentiometer (value between 0 and 1023)
Serial.print("Potentiometre :");
Serial.println(val);
val = map(val, 0, ADC_Max, 0, 180); // scale it to use it with the servo (value between 0 and 180)
Serial.println("Angle :");
Serial.println(val);
myservo.write(val); // set the servo position according to the scaled value
delay(200); // wait for the servo to get there
}
According to previous experiments, a colleague, and the documentation: yes it should work from 3V3 to 5V
I tried with 3 AA Batteries (4.5V). They power a LED but it won't work on the servo. I'll try with something a bit more reliable (I don't have an adequate battery holder just I just hold the AA next to each other), but I'm not sure that's the problem. I never had to use an independant power supply before just to power one or two servo of this size Plus it worked perfectly fine earlier in the week...
I usually do this project with an wemos ESP8266 but wanted to upgrade to an ESP32
I think you have been lucky so far. That servo can draw 550mA when stalled, quite enough to damage any ESP or arduino
If you couldn't make it work with 3 AA batteries then you had something connected wrong.
That's my second year in the job, second time I do it. All I can tell you is it's used several times a year in the company for at least 6 years, and no one really questioned it... But well, we are not all trained, and we do it for educational purposes. It's usually enough to have a battery pluged to the esp to run 2 servo, it's wifi, and a few leds. But it might explain some difficulties I had last year, and a few buried esp8266 ^^'
I made a more sturdy connection for my batteries (I repurposed a 8 AA holder to just hold 3 using crocodile clip). Even had an LED indicating me it's indeed supplied.
I keep checking my connection but I really can't figure it out.
I have my reading from the potentiometer. Servo is plugged to a 4.5V independant supply.
I just tried once again to plug the servo on a different pin on the esp32, changing it in the code too of course.
I have executed your sketch of post #1 in my 30-pin ESP32 Dev Board using SG-90 Servo. The Servo does not respond to 3.3V supply of the ESP32 Board. I connected the Servo to 5V supply of my Aruino NANO and now the Servo responses to the pot rotation.
Plus it worked perfectly fine earlier in the week...