In formatting multiple serial data with punctuation, I used two potentiometers attached to A0 and A1 and a switch attached to digital pin 2. I got my pot readings however I was having some trouble reading the switch. I thought it was the problem of my code but I think it is the way I set up my circuit. I first setup my switch like this: connecting a resistor from 5V to switch and then another line from switch to ground. When I pressed the switch, the digital reading doesn't change, it stays at 0. I tested with an LED the switch was able to turn the LED on and off successfully it just wouldn't change the reading at digital read.
Attempt 1 (fail)
so I reversed the resistor and the dark wire to have resistor going to ground from switch, and it worked successfully and was giving reading in the correct format as: pot1, pot2, switchState
Code:
const int switchPin = 2;
void setup() {
Serial.begin(9600);
pinMode(switchPin, INPUT);
}
void loop() {
int pot1 = analogRead(A0);
int pot2 = analogRead(A1);
int switchState = digitalRead(switchPin);
Serial.print(pot1);
Serial.print('\t');
Serial.print(pot2);
Serial.print('\t');
Serial.println(switchState);
}
Flow Control: Call and Response (Handshaking):
Code:
const int switchPin = 2;
void setup() {
Serial.begin(9600);
pinMode(switchPin, INPUT);
//sends out a message until it gets a byte of data from the remote computer
if (Serial.available() <= 0) {
//open serial port wait for "hello"
Serial.println("hello");
// send a starting message/Send a byte to request data
delay(300); // wait 1/3 second }
}
void loop() {
if (Serial.available() > 0) {
// Wait for one set of data
int inByte = Serial.read(); // Send a byte to request new data
int pot1 = analogRead(A0);
int pot2 = analogRead(A1);
int switchState = digitalRead(switchPin);
Serial.print(pot1);
Serial.print('\t');
Serial.print(pot2);
Serial.print('\t');
Serial.println(switchState);
}
}
In this handshaking code, however, I was still a little confused at the order of how each time one set of data is transmitted and received between the Arduino and computer (int inByte = Serial.read())
Draw dots with potentiometer:
I sent my potentiometer reading from analogRead(A0) as a numeric string (0-1023) to my p5 sketch using println(), and my p5 sketch receives the data as a string value with serial.readLine() and converted it to a number to store in inData and had inData mapped to 0-500, which corresponds to the number of dots on the canvas. As I turn the knob up and down, number of dots increases and decreases.
Arduino code:
int potValue;
void setup() {
Serial.begin(9600);
}
void loop() {
potValue = analogRead(A0);
Serial.println(potValue); //send as a numeric string (0-1023) using println
delay(1);
}
P5 code: https://editor.p5js.org/ada10086/sketches/Bycb6z39m
For application, I previewed two-way serial communication, and took one of my animation sketches from ICM class and have it controlled by Arduino.
In my original p5 sketch, I have two sliders one controlling the scaling speed and the other controlling the rotating speed of the squares, and also a button changing the color of the squares randomly. Each controlled by mouse dragging or clicking. So I thought it might be a good sketch to apply to serial communication as I can replace mouse interaction with potentiometers and button on my Arduino.
My circuit
Arduino code:
//serial input application
//sending multiple serial data with punctuation
//two potentiometers and one button controlling p5 animation
int pot1;
int pot2;
int buttonState;
void setup() {
Serial.begin(9600);
pinMode(2,INPUT); }
void loop() {
pot1 = analogRead(A0);
Serial.print(pot1);
Serial.print(",");
pot2 = analogRead(A1);
Serial.print(pot2);
Serial.print(",");
buttonState = digitalRead(2);
Serial.println(buttonState); }
my p5 code: https://editor.p5js.org/ada10086/sketches/r1oeUHTc7
My problem for this application is that my sketch jiggles a lot. when I apply change to one potentiometer to change scaling speed, for example, the other which controls the rotating speed would jiggles a little, and when I press the button, both parameters would jiggle, compared to accurate reaction of change in mouse actions in my original sketch. I ran println in my arduino serial monitor and noticed that there is a lot of jiggling in my sensor readings. I am not sure though if it is due to my hardware connection or problem in my serial communication.