A (much) better Pro Micro
The Bit-C is a microcontroller daughterboard featuring the Atmel ATmega32U4, designed for DIY keyboard enthusiasts. It features a sturdy through-hole USB-C connector that is more rugged than a standard USB micro B. It's only 1mm thick, so it sits slim and low. The Bit-C ships with the Atmel DFU bootloader, which is smaller and less finicky than the default Caterina bootloader. 100% of Bit-C units are exhaustively tested before shipping, ensuring you're spending your time building, not debugging. Best of all, it comes in white!
100% Pro Micro compatible
The Bit-C is a drop-in replacement for any Pro Micro MCU, including the Elite-C. With 1-1 GPIO pin parity, firmware builds don't need to be changed in order to swap in a Bit-C. The Bit-C is shipped with the lightweight Atmel DFU bootloader, making flashing with QMK a breeze. VBUS detection & backdrive protection are implemented for split keyboards, and a 500mA resettable fuse is included for protection.
Bit-C Comparison Table
|Bit-C PRO RP2040||Bit-C AVR 32U4|
|CPU architecture||RP2040: ARM Cortex M0+||ATmega 32U4: AVR|
|CPU clock||Dual core @ 133MHz||Single core @ 16MHz|
|GPIO Voltage Level||3.3V||5V|
|Flash size (program storage)||4MB on-board||16kB on-chip|
|RAM size (variable and data storage)||264kB on-chip||2.5kB on-chip|
|QMK firmware support||✅||✅|
|Arduino IDE support||✅||❌1|
|Electrically compatible with Bit-C PRO RP2040||✅||❌2|
|Electrically compatible with Bit-C AVR 32U4||❌2||✅|
1 The Bit-C AVR 32U4 can be used with Arduino IDE, but requires flashing a new bootloader.
2 The Bit-C PRO RP2040 and Bit-C AVR 32U4 cannot be "mixed and matched", as they use two different electrical voltage levels. For example, if building a split keyboard such as the SNAP, both Bit-Cs must be the same model. Boards connected over TRRS must also use the same MCU.
Included in the box
- Bit-C MCU
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