Meet Helios, 0xCB's rp2040 Controller with pro micro compatible pinout, 16MB (128Mbit) of flash, Dual ARM Cortex-M0 @133MHz, and 264kB SRAM.
Helios has an ESD protection chip onboard, supports VBUS detection for split keyboards, and you can select VBUS instead of raw for the 5V pin to hook up an external USB port with the included D+ and D- pads while maintaining ESD protection.
This product is based from an open source project by 0xCB, github source files HERE
2x pin headers
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