Non-Inverting Logic-Level-Shifting Heavy Load Control Unit. 3.3V to 12V, using 2 LEDs for opto-coupling. (For updates scroll to the end)
Controlling RT-Spark's built-in LCD and 3 LEDs using 5 momentary switches via GPIO on STM32F407ZGT6.
Budget-friendly 16-channel GPIO expander. MCP23017, I²C, chainable to 128 GPIOs, fits $2 PCB deal.
Experiments with the STM32 microcontroller with 5 switch controls to activate 3 LEDs in active low and in-built LCDs by RT-Spark
Industrial 16-channel GPIO expander with MCP23017. DIN-rail mountable, optoisolated, addressable via I²C.
A simple Python library to use stepper motors with GPIO Zero (modern interface to RPi pins).
Having the mental model of clock lines, shared highways, and packet handshakes is nice, but theory only gets you so far.
