Increasing the number of connectable peripherals using a microcontroller pin matrix

When connecting a large number of peripherals, such as a stepper motor driver, to a microcontroller, often the number of required pins exceeds the number of available pins, which leads to a change of microcontroller type or the need to create groups of microcontrollers. A method of connecting 16 A4988 stepper motor drivers to an ESP32 microcontroller is proposed. An optimisation matrix of control outputs is used to achieve the result, thus avoiding the use of more expensive drivers using data interfaces to control an individual motor.