TFT Color Displays#

When a project needs color, more pixels, or a display large enough to build a real UI on. TFT modules driven by controllers like the ILI9341 and ST7789 are the workhorses of embedded color graphics — they’re fast enough for responsive interfaces, cheap enough for hobby projects, and well-supported by the major graphics libraries. The complexity jumps compared to monochrome OLEDs: SPI configuration becomes critical, color format encoding matters, and pushing enough pixels for smooth updates often requires DMA.

What This Section Covers#

• Common TFT Controllers — ILI9341, ST7789, ST7735, and ILI9488: resolution, interface, and color depth compared, plus how to identify what controller a module actually uses.
• SPI Configuration & Wiring — SPI mode, clock speed tuning, the DC pin that makes TFT SPI different from normal SPI, level shifting, backlight control, and reset pin handling.
• Color Formats & Pixel Packing — RGB565 vs RGB666 vs RGB888: bit layout, byte ordering, endianness gotchas between MCU and display, and converting from 24-bit color.
• DMA & Throughput Optimization — Why CPU-driven SPI is slow for large displays, DMA transfer basics, double buffering, partial refresh, and the practical priority order for optimization.