Binary Arithmetic And Port Manipulation – Part Ii

Made by talofer99

About the project

One port to read them all

Project info

Difficulty: Easy

Estimated time: 1 hour

License: GNU General Public License, version 3 or later (GPL3+)

Items used in this project

Hardware components

	DFRobot I2C 16x2 Arduino LCD Display Module	x 1
	momentary push button	x 8
	Arduino UNO	x 1

Software apps and online services

	wokwi Arduino web simulator
	Arduino IDE

Story

In the first part I covered output of 8 LEDS using one port.

In this tutorial will use the port for input. Reading with one line of command the sate of 8 buttons.

Showing the difference in time it takes to perform this test.

Will also cover cool options of key combination, using the port input value.

I used WOKWI great web Arduino simulator the code from the video is available at https://wokwi.com/arduino/projects/284193979507933709

You can watch Part I here

For WOKWI great article on time counting in Arduino https://blog.wokwi.com/how-to-measure-the-speed-of-arduino-code/

For more read about binary arithmetic and its practical uses in Arduino

https://playground.arduino.cc/Code/BitMath

Some more info on ports in Arduino

https://www.arduino.cc/en/Reference/PortManipulation

Schematics, diagrams and documents

schmatics_bb_s7Ql4lY7uM.png

Code

Untitled file

//YWROBOT
//Compatible with the Arduino IDE 1.0
//Library version:1.1
#include <LiquidCrystal_I2C.h>

byte currentButtonState = 0;
byte prevButtonState = 99; // set to diffretn number then curren to trigger update on load

// set the LCD address to 0x27 for a 16 chars and 2 line display
LiquidCrystal_I2C lcd(0x27,20,4);  

void setup()
{
   // initialize the LCD
  lcd.init();

  // set pull ups
  for (int i = 0; i < 8; i++) {
    pinMode(i, INPUT_PULLUP);
  } //end for


  // Turn on the blacklight.
  lcd.backlight();


  //startTimer();
  //  DDRD = B00000000; // input
  //  PORTD = B11111111; // pullup
  //endTimerAndPrint();
  
}


void loop()
{
  // reset
  currentButtonState = 0;

  //collect state
  for (int i = 0; i < 8; i++) {
    currentButtonState |= (!digitalRead(i)) << i;
  } //end for

  //currentButtonState = ~PIND ; //read state

  // if state chnaged
  if (prevButtonState != currentButtonState) {
    //clear screen
    lcd.clear();

    // print hex
    lcd.setCursor(0, 0);
    lcd.print("0x");
    if (currentButtonState < 16) {
      lcd.print("0"); // in case we got single digit hex
    }//end if
    lcd.print(currentButtonState, HEX);

    // print binnary
    for (int i = 0; i < 8; i++) {
      lcd.setCursor((7 - i), 1);
      if (bitRead(currentButtonState, i)) {
        lcd.print("1");
      } else {
        lcd.print("0");
      } //end if
    } //end for

    // special key combination
    switch (currentButtonState) {
      case B10000001:
        lcd.noBacklight();
        break;
      case B01000010:
        lcd.backlight();
        break;

    } // end switch

  } //end if

  // set prev to current for change
  prevButtonState = currentButtonState;



  //startTimer();
  //currentButtonState = ~PIND ; //read state
  //endTimerAndPrint();
  //delay(1000);
}


void startTimer() {
  TCCR1A = 0;
  TCCR1B = bit(CS10);
  TCNT1 = 0;
}

void endTimerAndPrint() {
  unsigned int cycles = TCNT1;
  //clear screen
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Cyc: ");
  lcd.print(cycles - 1);
  lcd.setCursor(0, 1);
  lcd.print("Mic: ");
  lcd.print((float)(cycles - 1) / 16);

}

Credits

talofer99

Maker @ heart

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Binary Arithmetic And Port Manipulation – Part Ii

About the project

Project info

Items used in this project

Hardware components

Software apps and online services

Story

Schematics, diagrams and documents

schmatics_bb_s7Ql4lY7uM.png

Code

Untitled file

Credits

talofer99

Leave your feedback...

Shop

Project Hub

Video

Blog

Shop home

3D printing

Single Board Computers

Development kits

Sensors

Internet of things

Robotics

Accessories

Product of the Week

Electromaker Educator

The Electromaker Show

The Electromaker Podcast

Binary Arithmetic And Port Manipulation – Part Ii

About the project

Project info

Items used in this project

Hardware components

Software apps and online services

Story

Schematics, diagrams and documents

schmatics_bb_s7Ql4lY7uM.png

Code

Untitled file

Credits

talofer99

Leave your feedback...

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