Arduino compatible development boards

Arduino Pro Mini

Arduino Pro Mini

As cheap as it gets! Arduino Pro Mini clones are probably the cheapest solution for semi-permanent solutions. Small and extra cheap. Arduino Pro Mini lacks USB-to-serial converter, but that is not a big deal since you probably do not need USB after flashing and setting it up. And you can do development on other boards with USB. It comes in two versions: 5V 16MHz and 3.3V 8MHz.

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Arduino Pro Micro

Arduino Pro Micro

Arduino Pro Micro is a slightly more advanced version of Pro Mini. It keeps a similar form factor but brings a few changes: ATmega32u4 instead of ATmeage328 and dedicated USB ports. On a hardware level, different MCU offers more pins with hardware interrupts and in general, better experience. It's more expensive than Pro Mini, but it's easier to develop thanks to USB port and in general is a more advanced design.

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DOIT ESP32 development board

DOIT ESP32 development board

When Arduino and AVR based development boards are not enough, ESP32 to the rescue! Much more RAM, flash, 2 cores, WiFi, Bluetooth, and a flexible IO system. Can be programmed with C, Python, Lua and even Arduino. They are super cheap for the value and allow to make amazing DIY projects. You can read more about ESP32 on this site as well.

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TTGO ESP32 with OLED display and LiPo charger

TTGO ESP32 with OLED display and LiPo charger

Oh, did I already mentioned that some ESP32 development boards come with build in OLED? It might not be big since it's only 128×32 pixels, but it's already there. It is also possible to power this board using 1S 3.7V LiPo battery? It even as a built-in charger, so the LiPo will be charged when USB power is used!

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