The most popular and common DIY keyboard controller!

An Arduino clone based on the Atmel Atmega32u4 MCU

Specification

• USB port (Select USB-C or USB Mini B connector)
• Standard 24-pin interface, fit's many (most?) DIY keyboard designs
• Atmega32u4 5V & 16 Mhz (The most common used on keyboards)
• Serial, I2C, SPI, PWM and more
• 18 usable IO pins for your keyboard

Physical fitment

The original design of the Pro Micro with the USB Mini B connector, and the original outline, as shown in the image above (blue Pro Micro), has a shorter top portion extending past the top hole, than most USB C versions (shown in purple). This means that the USB C one's will not always fit custom 3D printed cases etc, as the USB port is pushed outside the case.

Unfortunately there is no real standardization on Pro Micro controllers in general as it's an open source design, and it is being copied sometimes form a copy. This also means that the USB C variants are pretty much different from seller to seller, ar at least between design variants. The ones I sell are purposely selected to be as short as possible, to fit the designs made for the 'original' outline.

Consider an upgrade!

The original Pro Micro is still the 'gold standard' that a lot of keyboards are still designed for, and the footprint will live on forever, with all the older designs still available for it. But the Atmega32u4 MCU is at this point a fair bit limited on run time memory/flash storage, and outright clock performance, being only an 8-bit core. And with demand vaning, and production numbers dropping, prices are in fact going up, and compared to other offerings, they are becoming 'expensive' when you look at the 'bang-for-buck' comparasions.

So with that in mind, I highly recommend considering using the RP2040 powered clone instead for your keyboard.

What's included

As standard, these are delivered in a sealed ESD bag, with the 2 pinheaders just like any Pro Micro clone.

I'm merely reselling these AS-IS to make it a one-stop-shop for building your keyboard.

Please note! You can likely find them cheaper on AliExpress or similar if you are willing to order from various sources or if bying in bulk. I'm merely covering my expenses, shipping/taxes etc, with no measurable profit on these.

Optional bootloader

As an added option, the Pro Micro can be delivered reflashed with a minimal bootloader. This gives you a lot more usable memory space for advanced QMK keymaps or using VIAL.

Using a Pro Micro controller is a very good 'easy' option as a beginner or for a low cost build, but with more and more advanced features added to QMK needing more memory to compile, or using VIAL for dynamic real-time keymapping, the Atmega32u4 is quickly running out of usable memory. The 'standard' Caterina bootloader is rather old code, and while convenient as it is the expected bootloader, working with any pre-compiled firmware out-of-the-box, it's using a fair amount of memory for not a lot of actual functionality.

Switching to a more modern, efficent bootloader gives you a lot more usable memory, but requires you to use an external programmer, as this cannot be flashed using the USB port and QMK Toolbox. nanoBoot, is a tiny HID-bootloader, meaning no additional drivers needs to be installed on your OS, and at just 512kB it's far smaller than Caterina with near identical functionality and in my experience better performance.

Using an external programmer can be daunting as a beginner, and not everyone owns one. (However an additional Pro Micro can be used as one!) So when purchasing a controller for your keyboard build, you can choose to have it pre-flashed with nanoBoot, ready to use as normal flashing the userspace firmware (QMK/VIAL) as normal using QMK toolbox, with minimal editing of the source, or using the pre-compiled VIAL firmware for keyboard designs sold in this shop.

nanoBoot bootloader

• https://github.com/osamuaoki/nanoBoot
• Only 512kB, giving you more usable memory
• Fully compatible with QMK/VIAL (need's firmware re-config/compile)
• HID-bootloader, no OS-side driver installation needed
• Userspace firmware can be flashed with QMK Toolbox as normal

Normal handling time is 3 - 5 working days, not including build items (Those usually take 1 - 2 weeks).

Shipping is done with insured/signed for parcels, where no such service is available the parcel is sent as insured parcel, but may not be fully traceable the entire transit. If no insured or traceable service is available, parcels will be sent as uninsured/untraceable at the buyers responsibility. All of which is clearly stated on checkout.

All packets are represented to courier services and customs at their true sale value, and all responsibility for import fees, taxes and tariffs lie with the buyer.

The SE/EU "Act on Distance Contracts and Off-Premises Contracts (SFS 2005:59)" allows returns of the items in undamaged (unsoldered!) condition within 14 days of receiving it. Return shipping on returned items are the responsibility of the buyer.