I2C vs SPI vs UART: Wiring, Speed, and How to Choose

A side-by-side comparison of the three serial buses every microcontroller project runs into — I2C, SPI and UART — across four axes: number of signal lines, speed, how many devices you can hang off them, and wiring distance. Includes a decision flow and what to look for on a scope.

July 20, 2026 · 20 min · 

STM32 Series #10: DMA — Transfers That Free the CPU

Stop having the CPU send bytes one at a time — let DMA handle everything. By DMA-ifying UART transmission, the CPU is freed to do real work. Episode 10 builds intuition for throughput, latency, and bus contention.

April 30, 2026 · 16 min ·