Can still be set to use 3.3V power and logic by soldering a jumper on the bottom.Upgraded USB to serial converter from CP2104 to CP2102 - same great reliable drivers!.Additional STEMMA QT port for plug and play I2C connections.Same pinout and size, same mounting hole locations - drop-in compatible!.Same ATmega328 chip, running at 16 MHz, which makes it compatible with all Arduino UNO based libraries, codes and examples.It still features the ATmega328 chip and is drop-in compatible with the original METRO Mini, but has many upgrades and improvements:

The V2 is a significant redesign, enough, so we consider it a completely new product. Recently we had to redesign this board to move from the obsolete CP2104 to the available CP2102N, and one thing led to another, and before you know it we made a completely refreshed design: the Adafruit METRO Mini 328 V2. For example, the construction of a solar food dryer by industrial arts students is described.One of our star development boards is the Adafruit METRO Mini 328, an excellent lil fellow that lets you make your Arduino-based project tiny. General areas addressed include energy sources, alternative energy sources, energy conservation, solar collectors/houses, fuels, utilities, and others addressing the needs of students in or subject matter focus of the areas previously indicated. Presented in the reports are energy-related activities, lessons, units, programs, information, and comments on the impact of the project on students. Reports, related to the project's third objective, are grouped by the following areas: primary intermediate secondary home economics secondary industrial arts secondary mathematics secondary science and secondary social studies. Included in this document are individual reports from teachers who participated in the project. Objectives of the Northern New Mexico Energy Education Project were to: (1) improve teachers' knowledge of energy-related subject matter and energy-related educational materials (2) develop continuing communication and cooperation between elementary and junior high staffs and the university on energy-related matters and (3) provide follow-up technical assistance to classroom teachers to prepare students for roles as citizens and consumers and to provide information on careers in energy-related fields.

Adafruit trinket 5v first project