nRFkbd allows you to build a completely wireless split keyboard with optional USB connectivity for data and charging. The board is designed around Holyiot-18039 module with nRF52840 MCU.

Features:

• 18 GPIO pins, which can be also used for SPI, I2C, ADC and other peripherals. 5 more GPIOs are available as solder points.
• Native USB and Bluetooth.
• Power supply from USB or a Li-ion battery.
• Li-ion battery charger.
• Secondary voltage configurable to: 1.8V, 2.1V, 2.4V, 2.7V, 3.0V, 3.3V (VDD_NRF pin).
• PCB antenna, optional external IPX antenna.
• Board dimensions: 57mm x 16mm x ~5mm.

This is a work-in-progress project. It has not been tested yet. ETA: Feb, 2022.