RF Remote Controlling a Servo Motor at Different Angles

Using Arduino Project Guidance
#1

Hello,

I am working on a project that includes an Arduino, a 4 button key fob, and a servo motor. Although i have 4 buttons i only need to use the A,B,C buttons. I am trying to make it so each button have a certain task. For “A” i want it to move 45 degrees, “B” i want it to go to 90 degrees, and “C” return back to 0. Any advise would be helpful.

Thanks

#2

Post details of your keyfob and the corresponding receiver.
Post your program and tell us what it actually does and what it should do that is different.

You question is a bit like "I want to paint my girlfriend's (or boyfriend's) portrait, please advise"

...R

#3

The keyfob is a 4-Button RF Remote Control - 315MHz and a simple RF M4 receiver from adafruit. Right now
my codes are below but i tried to put in another input but it wouldn’t let me. This code allows me to press the A and D button so when pressing A it allows it to move forward and for D allows it to go backwards. I need help adding another button B. Each would move at different positions so i would like A to move at 45 degrees and B move at 90 degrees and C will move back to 0 degrees.

#include <Servo.h>

byte pin = 8;
byte pin2 = 7;
int pos = 90;
Servo myservo;
void setup(){

pinMode(pin, INPUT); // initialize pins
pinMode(pin2, INPUT);

digitalWrite(pin, HIGH); // set internal pull up resistors
digitalWrite(pin2, HIGH);

myservo.attach(9);
}

void loop(){

int val = digitalRead(pin); // get the button values… low is pressed… high is not pressed
int val2 = digitalRead(pin2);

if (val == 0){
if (pos < 180 && pos > 0){

pos+=2;
} if (pos == 180){
pos = 178;
}

if (pos == 0){
pos = 2;
}
}

if (val2 == 0){
if (pos < 180 && pos > 0){

pos-=2;
}
if (pos == 180){
pos = 178;
}

if (pos == 0){
pos = 2;
}

}

myservo.write(pos);
delay(15);
}

#4

studentdo:
This code allows me to press the A and D button so when pressing A it allows it to move forward and for D allows it to go backwards. I need help adding another button B.

I don’t see button A or D or B in that code so how am I supposed to know how to help?

Post a link to the datasheet for your keyfob and receiver.

And please modify your post and use the code button </> so your code looks like this and is easy to copy to a text editor. See How to use the Forum

…R

#5

Do you see anything wrong with this:

pinMode(pin, INPUT); // initialize pins
pinMode(pin2, INPUT);

digitalWrite(pin, HIGH); // set internal pull up resistors
digitalWrite(pin2, HIGH);

Writing to input pins may be a problem.

Paul

#6

Paul_KD7HB:
Do you see anything wrong with this:

pinMode(pin, INPUT); // initialize pins
pinMode(pin2, INPUT);

digitalWrite(pin, HIGH); // set internal pull up resistors
digitalWrite(pin2, HIGH);

Writing to input pins may be a problem.

Paul

But very useful for enabling pull ups.

#7

AWOL:
But very useful for enabling pull ups.

Ok, I have always set them with initial definition.

Paul

#8

Robin2:
I don’t see button A or D or B in that code so how am I supposed to know how to help?

Post a link to the datasheet for your keyfob and receiver.

And please modify your post and use the code button </>

so your code looks like this

and is easy to copy to a text editor. See How to use the Forum

…R

#include <Servo.h>

int  A = 8; // button A input
int  D = 7; // button D input
int  B = 4; // button B input
int  servoPin = 9;

int angle = 90;
int change = 15; // this value determines how much the angle changes each time through the loop

Servo myservo;

void setup(){

 pinMode(A, INPUT);  // initialize pins
 pinMode(D, INPUT);
 pinMode(B, INPUT);
 
 digitalWrite(A, HIGH); // set internal pull up resistors
 digitalWrite(D, HIGH);
 digitalWrite(B, HIGH);
 myservo.attach(servoPin);
}

void loop(){

 if( digitalRead(A) == LOW) { 
   // here if increment switch pressed
   angle = angle + change;
 }
 if( digitalRead(D) == LOW) {
   // here if decrement switch pressed
   angle = angle - change;
 }  
  if( digitalRead(B) == LOW) {
   // here if decrement switch pressed
   angle = angle + change;
 }  
 angle = constrain(angle, 0, 180); // limit value of angle 
 myservo.write(angle);
 delay(20); 
}

I do not have access to the keyfob and receiver datasheet. I can’t seem to get my input button B to work. It works fine with A and D button inputs. Also, how can I make the angles precise and stop the servo motor from locking up so I don’t have to keep resetting it?

#9

studentdo:
I do not have access to the keyfob and receiver datasheet.

There is nothing I can suggest without seeing the datasheet. You, at least, have the advantage of having the hardware to experiment with

Why not write a separate short test program that just detects the different button presses and prints a short message on the Serial Monitor?

And this

int  A = 8; // button A input
int  D = 7; // button D input
int  B = 4; // button B input

is not a good system. Your program will be much easier to understand and debug if you do it like this

int  buttonApin = 8;
int  buttonDpin = 7;
int  buttonBpin = 4;

because then you don't need to write any comments to explain it.

...R

#10