Tinkerforge::BrickletLCD20x4 - Device for controlling a LCD with 4 lines a 20 characters
This constant is used to identify a LCD 20x4 Bricklet.
The get_identity() subroutine and the CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.
This constant is used with the register_callback() subroutine to specify the CALLBACK_BUTTON_PRESSED callback.
This constant is used with the register_callback() subroutine to specify the CALLBACK_BUTTON_RELEASED callback.
This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.
Creates an object with the unique device ID *uid* and adds it to the IP Connection *ipcon*.
Writes text to a specific line (0 to 3) with a specific position (0 to 19). The text can have a maximum of 20 characters.
For example: (0, 7, "Hello") will write *Hello* in the middle of the first line of the display.
The display uses a special charset that includes all ASCII characters except backslash and tilde. The LCD charset also includes several other non-ASCII characters, see the `charset specification <https://github.com/Tinkerforge/lcd-20x4-bricklet/raw/master/datasheets/standard_charset.pdf>`__ for details. The Unicode example above shows how to specify non-ASCII characters and how to translate from Unicode to the LCD charset.
Deletes all characters from the display.
Turns the backlight on.
Turns the backlight off.
Returns *true* if the backlight is on and *false* otherwise.
Configures if the cursor (shown as "_") should be visible and if it should be blinking (shown as a blinking block). The cursor position is one character behind the the last text written with :func:`WriteLine`.
The default is (*false*, *false*).
Returns the configuration as set by :func:`SetConfig`.
Returns *true* if the button (0 to 2 or 0 to 3 with hardware version >= 1.2) is pressed. If you want to react on button presses and releases it is recommended to use the :func:`ButtonPressed` and :func:`ButtonReleased` callbacks.
The LCD 20x4 Bricklet can store up to 8 custom characters. The characters consist of 5x8 pixels and can be addressed with the index 0-7. To describe the pixels, the first 5 bits of 8 bytes are used. For example, to make a custom character "H", you should transfer the following:
* ``character[0] = 0b00010001`` (decimal value 17) * ``character[1] = 0b00010001`` (decimal value 17) * ``character[2] = 0b00010001`` (decimal value 17) * ``character[3] = 0b00011111`` (decimal value 31) * ``character[4] = 0b00010001`` (decimal value 17) * ``character[5] = 0b00010001`` (decimal value 17) * ``character[6] = 0b00010001`` (decimal value 17) * ``character[7] = 0b00000000`` (decimal value 0)
The characters can later be written with :func:`WriteLine` by using the characters with the byte representation 8 to 15.
You can play around with the custom characters in Brick Viewer version since 2.0.1.
Custom characters are stored by the LCD in RAM, so they have to be set after each startup.
.. versionadded:: 2.0.1~(Plugin)
Returns the custom character for a given index, as set with :func:`SetCustomCharacter`.
Sets the default text for lines 0-3. The max number of characters per line is 20.
The default text is shown on the LCD, if the default text counter expires, see :func:`SetDefaultTextCounter`.
.. versionadded:: 2.0.2~(Plugin)
Returns the default text for a given line (0-3) as set by :func:`SetDefaultText`.
Sets the default text counter in ms. This counter is decremented each ms by the LCD firmware. If the counter reaches 0, the default text (see :func:`SetDefaultText`) is shown on the LCD.
This functionality can be used to show a default text if the controlling program crashes or the connection is interrupted.
A possible approach is to call :func:`SetDefaultTextCounter` every minute with the parameter 1000*60*2 (2 minutes). In this case the default text will be shown no later than 2 minutes after the controlling program crashes.
A negative counter turns the default text functionality off.
The default is -1.
Returns the current value of the default text counter.
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c' or 'd'.
The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|
To install Tinkerforge, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Tinkerforge
CPAN shell
perl -MCPAN -e shell install Tinkerforge
For more information on module installation, please visit the detailed CPAN module installation guide.