Test Any MCU Using Only 4 I/O Lines

MCU I/O and Performance Test with 4Btns & 4 LEDs using 5 Lines only.
Test virtually any MCU with as little as 4 digital I/O lines (even only 2 all be it tricky) for project suitability and performance.
When I start a new project I don’t like hooking up a lot of wires before making any progress on what I actually want to focus on. So I built a 4 buttons and 4 LED fixture, utilizing only 4 or 5 DIO lines, which could quickly be hooked up to any MCU. I built a couple of versions, using a few different combinations of various types of buttons and LEDs I had on hand. See …
The 4x4 test fixtures and software can not only be used to test and evaluate potential MCUs for your project but also be utilized as a basis for your project(s).
The related Arduino sketches preform operations to exercise Buttons, LED operation and lighting levels, timing, interrupts, analog and digital I/O, EEPROM storage, USB-Serial I/O and optionally buzzer &/or speaker.
I also provide a MCU Performance Benchmark, giving MCU Marks for the number of times a second a standardized set of I/O and processing operations (simulated project) can be performed.”

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