Review on OSOYOO Pro Micro ATmega32U4 Module Board: 5V/16MHz, 2 Row Pin Header, Arduino Compatible – Upgraded Version with ATmega328 Pro Mini Support by Jon Booth

Board works great. I didn't have any problems that I couldn't solve. Switch to my recommendation to use board definition "Leonardo". This avoids all the problems I had, no need to upload a new definition. Only the 5 pens Leonardo has are missing, so just don't use them. Also use macros for the RX and TX LEDs as pin 13 is one of the missing pins, plus an extra (active high) LED. ------------ Original review: ------ ------- However, I only gave 4 stars because of the lack of documentation. This board electrically replicates the SparkFun Pro Micro - 5V/16MHz, except for the RXLED and TXLED (at least on my board). both are red and the power LED is green. And the bootloader shows up as Arduino Mini which is confusing but works. I'm using the latest version of the Arduino system on Windows 10 which seemed to fix all driver issues and didn't need to download any drivers. I used the Arduino tool. to download SparkFun board definitions for "Pro Micro" that have pin definitions that are not recommended by Leonardo. (Leonardo should work, but there are pin definition issues.) BE EXTRA CAUTIOUS if you are using the "Pro Micro" board setting that when you select the board type, YOU ALSO have the processor selection in a separate Menu item on "ATmega32U4 ( 5V, 16MHz)". Otherwise the board will stop working. (Then it is necessary to perform an intricate and complex reset sequence using the reset pin and booting within a special 8 second window with the correct settings to reset the board so it works after the 8 second boot delay has expired .) Other problems are related and similar to the same problems with the Pro Micro and Leonardo itself. This board has the particular advantage that the user can transfer data over USB very quickly and can simultaneously output data over the serial RX, TX -Port to another process I've found this particularly useful when communicating with another system via serial data.