The Elite C and the Pro Micro are interchangeable. On most split keyboard kits, you can choose to either use two Pro Micros, two Elite Cs, or even a Pro Micro and an Elite C.
Pro Micros are cheaper than Elite Cs. So why use them at all? In this article I'll explain the pros and cons of using either.
About the Pro Micro
The original Pro Micro was designed by SparkFun, and is open source. It's a so-called breakout board, as it makes available (breaks out) the ports of the microcontroller onto larger, more accessible pins. A breakout board makes soldering a lot easier, and also allows you more options as for which breakout board to use.
Since the Pro Micro is open source, it is made by several factories and there are several variants available. The Pro Micro that we sell at splitkb.com is tested and verified to work in our kits.
Compared to the Elite C, a Pro Micro is relatively affordable. However, its Micro USB port is SMD mounted, meaning that it attaches to pads on the top of the Pro Micro only. Thus, the Pro Micro has a vulnerable USB port, that can tear off accidentally when unplugging the USB cable. Even so, it remains one of the most popular controllers today, since it's so affordable.
Enter the Elite C
The Elite C is a breakout board designed by someone who goes by the nickname That Canadian. It uses the same form factor as the Pro Micro, and is meant to be used as a replacement for the Pro Micro.
The Elite C is changed in several ways when compared to the Pro Micro. The most important distinction: the Elite C uses USB C. The port is through-hole mounted, meaning that the legs on the connector go through the PCB and connect on both sides. With the port being connected in this way, the Elite C has a strong and reliable USB port.
Other than that, the Elite C also has some other nifty features:
- An on-board reset button that's useful for testing or when your board otherwise doesn't have a reset button;
- Six extra pins broken out, so you can add extra functionality to your keyboard if you're keen to do so;
- It comes preflashed with the DFU bootloader which provides additional safeguards (won't allow overwriting itself, for instance) when flashing and makes flashing it faster overall;
- It has castellated pins so you can surface mount the controller on compatible keyboards.
So what should I use?
The Pro Micro and Elite C are completely interchangeable. This means that when it comes to the bare functioning of your keyboard, either will do completely fine.
The question then becomes, what should you use for your keyboard?
- If you're mainly concerned with cost, use two Pro Micros. Do consider socketing them so that you'll be able to easily replace it if the USB port inadvertedly breaks.
- If you're looking for added security and only use one side as the master, you can choose to use one Elite C on the master side and a Pro Micro on the slave. You'll primarily use USB C with your keyboard, and only sometimes need to flash changes to your Pro Micro with a Micro USB cable.
- If you're looking for convenience and aesthetics, or often use either side as master, use two Elite Cs. You'll be able to use the same USB C cable across halves so you won't need to dig for your Micro USB cable. They'll also look the same, which is nice if the Elite Cs are exposed like on many top-mounted keyboard builds such as the Kyria, Lily58 or Corne.
In all cases, socketing your microcontroller can be useful, so do consider reading Why would I want to socket my microcontroller? You can also read up on How do I socket a microcontroller?
I hope this article helps you decide what to use. Do you still have questions? Please feel welcome to ask by mail, Discord or through the chat in the bottom right corner.