Implementing U8x8 text mode in Arduino is incredibly straightforward. Below is a complete, production-ready example for a standard .
void setup() u8x8.begin(); u8x8.setFont(u8x8_font_artosserif_8x8); // Select your u8x8 font
To understand why u8x8 fonts exist, you have to understand the hardware they target. Most small OLEDs (like the SSD1306) and LCDs (like the HD44780) are inherently pixel-based. However, the u8x8 approach abstracts the pixels into .
U8g2 fonts follow a consistent naming convention that indicates their properties. The suffix at the end of each font name tells you what character set is included: u8x8 fonts
The library includes special drawing functions such as draw2x2String() that automatically scale a standard 8x8 font by a factor of 2 in both dimensions. This feature is particularly useful for displaying large, attention-grabbing text while using standard font definitions.
Each character in a U8x8 font is defined by exactly . Each byte represents a vertical column of 8 pixels, where the Least Significant Bit (LSB) is the top pixel and the Most Significant Bit (MSB) is the bottom pixel. 2. Workflow to Export Custom Fonts
The font only includes ASCII 32-127. Extended characters require specific fonts with "extended" or "cyrillic" in the name. Fix: Use u8x8_font_8x8_cyrillic or u8x8_font_cp437 for IBM Code Page 437 symbols. Implementing U8x8 text mode in Arduino is incredibly
| Suffix | Meaning | Description | |---|---|---| | _tf | Full | All characters from 32 to 255 | | _tr | Reduced | Only characters from 32 to 127 (basic ASCII) | | _te | Extended | European character set | | _t_all | All | All available characters | | _t_cyrillic | Cyrillic | Cyrillic character set | | _t_hebrew | Hebrew | Hebrew character set | | _t_symbols | Symbols | Symbol characters | | _mf , _mr , etc. | Monospace | Same as above but monospaced |
: Swapping out u8x8_font_chroma48_hf (Full) for u8x8_font_chroma48_hn (Numeric) can save several kilobytes of flash memory.
One of the more powerful features of the U8x8 library is the ability to access and modify individual glyph data on the fly. The function u8x8_get_glyph_data() allows you to copy an 8×8 character tile into a buffer, modify it, and then redraw it. A typical Arduino implementation might look like: Most small OLEDs (like the SSD1306) and LCDs
u8x8.enableUTF8Print();
If the default font sets do not match your project's visual style, you can create your own custom 8x8 font arrays. 1. The Byte Mapping Logic
The typical conversion command looks like: bdfconv.exe -v -f 2 -m "65-68" NMV1.bdf -o NMV1.c -n NMV1
The font names follow a strict naming convention in the code (e.g., u8x8_font_chroma48_hf ). Here are some of the most widely used categories: 1. Standard and Terminal Fonts
u8x8.setFont(u8x8_font_open_iconic_all_1x1); // The character '@' maps to a specific icon in this font array u8x8.drawGlyph(0, 0, 64); Use code with caution. Creating Custom 8x8 Fonts