K2FontLCD

K2FontLCD is a Windows desktop application for designing custom character sets for low-resolution monochrome LCD screens. Unlike operating system fonts, which cannot be used directly on microcontrollers, K2FontLCD generates the exact binary data array your firmware needs to display text on screen.

Each character is represented as a bitmap of up to 48×64 pixels where each pixel can be on (black) or off (white). The program supports up to 26 simultaneous characters (digits 0–9, uppercase A–Z or lowercase a–z) and exports them as a code block ready to paste into the IDE.

The typical process for creating a font from scratch follows these steps:

1. Choose the character set — Select whether you will work with digits (0–9), uppercase letters (A–Z), lowercase letters (a–z) or graphic digits.

2. Define the bitmap size — Set the width and height in pixels for each character using the Image Size controls.

3. Configure the base font — Choose a system font, its size, bold or italic style, and adjust the initial position.

4. Review and edit each character — Click on any character to see it enlarged and manually touch up its pixels if needed.

5. Save the project — Save your work in .K2Font format to resume it later.

6. Generate the code — Press Generate Code to export the data array to the clipboard.

Image Size defines the pixel dimensions of each character's bitmap. All characters in the set share the same size.

The indicators next to each bar show the current size in pixels. If the resulting size is insufficient for the chosen font, the indicator turns red as a warning.

The Numbers, Uppercase and Lowercase modes generate characters from a font installed on Windows. The program automatically draws each corresponding ASCII character inside the bitmap.

The Classic Digits and Modern Digits modes do not use system fonts. Instead, the program draws the numbers 0–9 using its own segment-based algorithm, similar to 7-segment displays but adapted to pixels. They are ideal for scoreboards, counters and digital clocks.

In this mode the Line Thickness control replaces the font selector and controls the segment thickness. The Margin control adjusts the internal separation of the segments from the bitmap edge.

Only available in text modes (Numbers, Uppercase, Lowercase).

These control how the font is placed inside each character's bitmap.

Manual position

If Auto Size is off, the Font Position X and Y bars allow you to manually shift the font inside the bitmap. The displayed value indicates the displacement in pixels relative to the centre of the bitmap.

The program shows all characters of the set in the central panel. You can select the active character in three ways:

• Direct click on the character thumbnail in the central panel.
• Click on the example text — each character of the example text is also clickable.
• Previous and Next buttons to navigate sequentially through the set.

The selected character is highlighted in dark blue on gold background in the thumbnail panel, and shown enlarged in the left editing panel. The Char indicator shows the corresponding ASCII symbol.

Clicking on any pixel in the zoom panel (left) activates edit mode. The first time you edit, the program warns that the bitmap size cannot be changed once editing has begun.

Brush behaviour

• The first click determines the edit colour: if the pixel was black it becomes white, and vice versa.
• While holding the button and dragging, all pixels the cursor touches take the same colour as the first one.
• Releasing the button ends the painting operation.

The four directional buttons (Up, Down, Left, Right) shift all pixels of the active character one position in the indicated direction. Pixels that exit from one edge are lost; pixels entering from the opposite edge are white (off).

The program maintains a history of up to 20 undo steps per editing session. Press Ctrl+Z to undo the last operation.

Press the Generate Code button to open the export dialog. The generated code is automatically copied to the clipboard ready to paste into your IDE.

Before generating, the program checks that a start label has been defined. This label is used as a prefix for each character name in the generated code (for example, with label "F_", character 'A' will be called "F_A").

The export dialog allows you to configure how the code is generated according to the target LCD controller.

K2FontLCD saves the complete work state in project files with the .K2Font extension: all character bitmaps, set size, font, position, styles and the selected character.

.K2Font file association

From Configuration → Associate files .K2Font you can register the .K2Font extension in Windows so that double-clicking a .K2Font file automatically opens it with K2FontLCD. This operation requires administrator permissions; if the program is not running as such, it will offer to relaunch with the necessary permissions.

Interface language

The interface is available in Spanish and English. Change the language from Configuration → Language. The preference is saved automatically.

1. Why is this software not digitally signed?

This software is a completely free, non-profit project. Obtaining and maintaining an official Microsoft digital signature involves a high annual cost that is unfortunately not viable for a free project.

2. How can I verify that the application is safe?

Transparency is our priority. Before running the installer, you can scan it on VirusTotal or any other external security tool. There you can verify, using dozens of antivirus engines simultaneously, that the file is 100% free of viruses and malware.

3. Windows is blocking the installation and won't let me continue — what should I do?

This happens due to a Windows 11 feature called Smart App Control. This tool automatically blocks any software that is not digitally signed, regardless of whether it is safe or not. As an independent developer, the system prevents installation by default.

To install the application, you can temporarily disable this feature by following these steps:

1. Open the Windows Security menu.

2. Go to the App & browser control section.

3. Click on Smart App Control settings.

4. Change the status to Off.