Keypad

Keypad

The Hardware and software for a simple 3x4 Keypad featuring a USB-C Interface

https://wiki.seeedstudio.com/Seeeduino-XIAO/#resourses
https://grabcad.com/library/5x5mm-smd-tactile-button-1
https://grabcad.com/library/kailh-polia-switch-cherry-mx-compatible-1

How to use

Setup

• Install the newest version of arduino IDE
• In arduino IDE, under preferences add this board URL

https://files.seeedstudio.com/arduino/package_seeeduino_boards_index.json

• Install the newest version of the Seeed SAMD Boards package from the boards manager
• Install the newest version of the Keyboard library from the library manager
• Clone or download Keypad into your Arduino project folder

Changing keyboard layout

Keyboard.begin(KeyboardLayout_de_DE);

The keyboard layout can be changed in Keypad.ino by substituting KeyboardLayout_de_DE with any of the following layouts supported by the arduino keyboard library:

KeyboardLayout_de_DE
KeyboardLayout_en_US
KeyboardLayout_es_ES
KeyboardLayout_fr_FR
KeyboardLayout_it_IT
KeyboardLayout_sv_SE
KeyboardLayout_da_DK

Editing macros

Open Keypad.ino with the arduino IDE. Functions of the keypad can be configured by editing the code inside the switch statement inside loop(). Two examples are already filled in.

switch (keys[j][i]) {
    //special macros
    case 1:
        numpadAscii(i, j, 231);
        break;
    case 10:
        textMacro(i, j, "max.mustermann@generic-mailservice.com");
        break;

    //all other keys: press key according to keyMap
    default:
        singleKeypress(i, j);
        break;
}

To configure a specific key, look up its number in the keys variable:

const int keys[3][4] = {
  { 1, 2, 3, 4 },
  { 5, 6, 7, 8 },
  { 9, 10, 11, 12 }
};

Then, add a special case to the switch statement (in this example key number 2 was chosen):

case 2:

    ...

    break;

Predefined macros

Several common macros are already implemented:

act as single key:

case 2:
    singleKeypress(i, j, keycode);
    break;

where keycode is a either an integer corrosponding to a key or one of the following special keys:

KEY_LEFT_CTRL
KEY_LEFT_SHIFT
KEY_LEFT_ALT
KEY_LEFT_GUI
KEY_RIGHT_CTRL
KEY_RIGHT_SHIFT
KEY_RIGHT_ALT
KEY_RIGHT_GUI

KEY_UP_ARROW
KEY_DOWN_ARROW
KEY_LEFT_ARROW
KEY_RIGHT_ARROW
KEY_BACKSPACE
KEY_TAB
KEY_RETURN
KEY_MENU
KEY_ESC
KEY_INSERT
KEY_DELETE
KEY_PAGE_UP
KEY_PAGE_DOWN
KEY_HOME
KEY_END

Type text macro:

case 2:
    textMacro(i, j, "your-text-here");
    break;

Ascii character macro (where 231 is an example):

case 2:
    numpadAscii(i, j, 231);
    break;

Custom code for macro

activate while key is held

case 2:
    if (keysPressed[i][j]) {

    ...
    
    }
    break;

activate on rising edge (keypress)

case 2:
    if (keysPressed[i][j] && !lastKeysPressed[i][j]) {

    ...
    
    }
    break;

Flashing

After changes have been made to Keypad.ino the program has to be uploaded to the microcontroller.

In Arduino IDE:

• select Seeduino XIAO as your board
• select the correct Port
• upload the sketch