TELEPHONE KEYPAD LAYOUT HOW TO
TELEPHONE KEYPAD LAYOUT INSTALL
TELEPHONE KEYPAD LAYOUT SERIAL

TELEPHONE KEYPAD LAYOUT INSTALL

To install it, download the ZIP file below, then go to Sketch > Include Library > Add. This library is nice because it includes most of the functions available in the standard LiquidCrystal library. To use an I2C enabled LCD on the Arduino, youвЂ™ll need to install the LiquidCrystal I2C libraryВ by Marco Schwartz.

That takes up a lot of pins, so IвЂ™m going to use an I2C enabled LCD because it only needs 4В wires to connect to the Arduino. 4X4 keypads use 8В pins and 3X4 keypads use 7 pins.

TELEPHONE KEYPAD LAYOUT HOW TO

Now letвЂ™s see how to print the key presses on an LCD. For example, say your keypad has a column of letters on the left instead of the right. If your keypad has a different layout, you can define which characters are printed when you press a button. The characters are laid out just as they appear on the keypad. Lines 6-11 define which characters are printed when a particular button is pressed on the keypad. Lines 3 and 4 in the code above setВ the number of rows and columns on the keypad. If youвЂ™re using a 3X4 keypad, you can useВ this code: #include Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS) OnceВ the Keypad library is installed, you can upload this code to the Arduino if youвЂ™re using a 4X4 keypad: #include Click on the library, then click install. To install the Keypad library, go toВ Sketch > Include Library > Manage Libraries and search for вЂњkeypadвЂќ. This library takes care of setting up the pins and polling the different columns and rows. WeвЂ™ll use the Keypad library by Mark Stanley and Alexander Brevig.

TELEPHONE KEYPAD LAYOUT SERIAL

Programming the KeypadДЇor a basic demonstration of how to setup the keypad, IвЂ™ll show you how to print each key press to the serial monitor. Repeat this process for each one of the other columns until you have each one mapped out. Now press down another button in the same row, and insert the positive wire into each one of the other pins. The pin that makes the LED light up is the pin thatвЂ™s connected to that buttonвЂ™s column. Now insert the positive wire into each one of the remaining pins.

Now press and hold any one of the buttons in that row. ToВ figure out which pins the columns are connected to, insert the groundВ wire into the pin you know is row 1. Now move the groundВ wire over to the next pin, press a button in a different row, and repeat the process above until youвЂ™ve found the pin for each row. If the LED lights up on a different pin, itВ means the groundВ wire is inserted into the row 1 pin.В If none of the buttons in row 1 make the LED light up, the groundВ wire is not connected to row 1. If the LED lights up at one of the pins, press and hold another button in row 1, then insertВ the positive wire into each one of the other pins again. Now insert the positive (red) wire into each one of the other pins. Press any button in row 1 and hold it down. Insert the groundВ (black) wire into the first pin on the left. First,В find out which keypad pins are connected to the button rows.

Telephone keypad layout