Archives for 

lcd

Arduino LCD and Keypad Shield

lcd keypad shield - arduino shield

lcd keypad shield – arduino shield

Arduino LCD Shield that widely used is made by DFRobot.

DFRobot combines LCD Shield and Keypad Shield in one module. This LCD shield using a 16×2 character LCD components, and 5 buttons that you can use to create a menu option on your project.

This Arduino LCD keypad shield can be mounted on the Arduino Uno. And like Arduino shield in general, you can install it by plugging in the top of Arduino Uno.

lcd keypad shield - datasheet

lcd keypad shield – datasheet

You will still be able to use all Arduino pins, although it is installed by sticking the Arduino Board. This diagram illustrates that this LCD Arduino provide pins which replaces the function of the pins on the Arduino board. You can still access + 5V, 3.3V, and ground pin, which has been provided on the LCD keypad shield.

PinFunction
Analog 0Button (select, up, right, down and left)
Digital 4DB4
Digital 5DB5
Digital 6DB6
Digital 7DB7
Digital 8RS (Data or Signal Display Selection)
Digital 9Enable
Digital 10Backlit Control

It uses 8 pin arduino, and you can take advantage of the other pins for sensors or other purposes. Pin A1 to detect the five buttons, while the digital pin 4 to 10 is used to control the LCD.

lcd keypad board - arduino shield

lcd keypad board – arduino shield

Source Code for Arduino LCD Keypad Shield

lcd keypad shield - datasheet

lcd keypad shield – datasheet

Here is the Arduino programming tutorial for LCD keypad shield. Arduino LCD keypad shield used is described in this article.

How to install LCD keypad shield on arduino uno simply by plugging in the arduino board. This tutorial will explain 3 arduino program. The first source code explains how to display characters on the LCD shield. Source code number two explains how to read keys on the keypad shield. And source code number three is the incorporation of lcd shield source code and keypad shield source code.

Source code to display characters on the LCD

//Sample using LiquidCrystal library
#include <LiquidCrystal.h>

// select the pins used on the LCD panel
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
void setup()
{
lcd.begin(16, 2); // start the library
lcd.setCursor(0,0);
lcd.print(“avrchip.com”); // print a simple message
}

void loop()
{
lcd.setCursor(9,1); // move cursor to second line “1” and 9 spaces over
lcd.print(millis()/1000); // display seconds elapsed since power-up

}

 

 

Source code to read keys on keypad shield

//Sample using LiquidCrystal library
#include <LiquidCrystal.h>
// define some values used by the panel and buttons
int button = 0;
int adc_key_in = 0;
#define btnRIGHT 0
#define btnUP 1
#define btnDOWN 2
#define btnLEFT 3
#define btnSELECT 4
#define btnNONE 5

// read the buttons
int read_LCD_buttons()
{
adc_key_in = analogRead(0); // read the value from the sensor
// my buttons when read are centered at these valies: 0, 144, 329, 504, 741
// we add approx 50 to those values and check to see if we are close
if (adc_key_in > 1000) return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result
// For V1.1 us this threshold
if (adc_key_in < 50) return btnRIGHT;
if (adc_key_in < 250) return btnUP;
if (adc_key_in < 450) return btnDOWN;
if (adc_key_in < 650) return btnLEFT;
if (adc_key_in < 850) return btnSELECT;

// For V1.0 comment the other threshold and use the one below:
/*
if (adc_key_in < 50) return btnRIGHT;
if (adc_key_in < 195) return btnUP;
if (adc_key_in < 380) return btnDOWN;
if (adc_key_in < 555) return btnLEFT;
if (adc_key_in < 790) return btnSELECT;
*/
return btnNONE; // when all others fail, return this…
}

void setup()
{

}

void loop()
{
button = read_LCD_buttons(); // read the buttons
}

 

LCD keypad shield source code

//Sample using LiquidCrystal library
#include <LiquidCrystal.h>

// select the pins used on the LCD panel
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

// define some values used by the panel and buttons
int lcd_key = 0;
int adc_key_in = 0;
#define btnRIGHT 0
#define btnUP 1
#define btnDOWN 2
#define btnLEFT 3
#define btnSELECT 4
#define btnNONE 5

// read the buttons
int read_LCD_buttons()
{
adc_key_in = analogRead(0); // read the value from the sensor
// my buttons when read are centered at these valies: 0, 144, 329, 504, 741
// we add approx 50 to those values and check to see if we are close
if (adc_key_in > 1000) return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result
// For V1.1 us this threshold
if (adc_key_in < 50) return btnRIGHT;
if (adc_key_in < 250) return btnUP;
if (adc_key_in < 450) return btnDOWN;
if (adc_key_in < 650) return btnLEFT;
if (adc_key_in < 850) return btnSELECT;

// For V1.0 comment the other threshold and use the one below:
/*
if (adc_key_in < 50) return btnRIGHT;
if (adc_key_in < 195) return btnUP;
if (adc_key_in < 380) return btnDOWN;
if (adc_key_in < 555) return btnLEFT;
if (adc_key_in < 790) return btnSELECT;
*/
return btnNONE; // when all others fail, return this…
}

void setup()
{
lcd.begin(16, 2); // start the library
lcd.setCursor(0,0);
lcd.print(“Push the buttons”); // print a simple message
}

void loop()
{
lcd.setCursor(9,1); // move cursor to second line “1” and 9 spaces over
lcd.print(millis()/1000); // display seconds elapsed since power-up
lcd.setCursor(0,1); // move to the begining of the second line
lcd_key = read_LCD_buttons(); // read the buttons

switch (lcd_key) // depending on which button was pushed, we perform an action
{
case btnRIGHT:
{
lcd.print(“RIGHT “);
break;
}
case btnLEFT:
{
lcd.print(“LEFT “);
break;
}
case btnUP:
{
lcd.print(“UP “);
break;
}
case btnDOWN:
{
lcd.print(“DOWN “);
break;
}
case btnSELECT:
{
lcd.print(“SELECT”);
break;
}
case btnNONE:
{
lcd.print(“NONE “);
break;
}
}

}