Puchi-BLE - Wireless Microcontroller (Pro Micro replacement)

Features

• nRF52840 wireless module
• Li-Po battery charger (4.2V Lithium @ 100mAh)
• USB Type-C (data and charing)
• Pro-Micro drop-in replacement (same size 18x33mm, pinout)
• Support for QMK (nrf52 fork) and ZMK (recommended)
• USB Mass Storage for firmware update
• True wireless split keyboard (no TRRS cable, or separate receiver)
• Also wired split keyboard with USB-C and Serial/I2C connection
• Comes with Adafruit nRF52 Bootloader (UF2 Mass Storage updates and DFU serial)
• System requirements: Bluetooth >4.2 for ZMK

Variant:

• Standard (thin): Mid-Mount USB-C connector, castellated holes, pattern on the backside
• With On/Off switch: On/Off switch for battery, higher as the Standard variant

The Puchi-BLE comes without header pins, to keep the price low as possible.
I highly reccommend to use the "Single Row Sockets" from Mill-Max, the cheaper alternative, or the "Spring-loaded pin headers".
You can find the standard pin header here.

Difference to the nice!nano:

• Certified Bluetooth module (CE, FCC and ROHS)
• Optimised ceramic antenna for high signal strength and low levels of interference
• On/Off switch to extend battery life (only Variant with switch)
• Open Source

Battery (read carefully)

• Puchi-BLE supports 1S LiPo batteries (4.2V)
• Only use LiPo batteries with a protection circuit, because the Puchi-BLE has no low voltes (discharge) protection for batteries
• A 301230 (3.0 x 12 x 30 mm) LiPo batterie fit between 4.5mm tall pin sockets
• Connect the batterie to B+ and B-, or RAW and GND (these pairs of pins are internally connected)
• Avoid reverse polarity (nRF52840 chip is usually destroyed first)
• Note that a few keyboards have RAW and VCC pins connected together (namely Helix and Gherkin), and will kill the controller (RAW pin is for the charger only). You may just not solder RAW pin to the keyboard as a workaround.

FAQ

• Do i need a TRRS cable to connect the split keyboard halfs?

  No, the slave side connects wireless to the master side. Optional you can use a cable (no charge over TRRS cable).

• What's the battery life?

  Approximately 2weeks with a 100mAh battery (no oled, or led‘s).

• Is there a lag while typing?

  Bluetooth devices can reach a latency of 1.3 ms. Lower latency means more power drain and reduce the battery life.

• Is it possible to switch between Bluetooth devices?

  Yes, QMK and ZMK have support for up to 5 Bluetooth profiles.

• What batteries work with the Puchi-BLE?

  LiPo batteries with 1S. Also important is that the LiPo batterie has a protection circuit (low voltes / discharge)

• Are batteries available in the shop?

  No, due to the german law, i don’t offer batteries in the shop. You can get LiPo batteries on Ebay and Aliexpress.

• What are the EXT_VCC and EXT_GND? Are they the same pins as VCC and GND?

  Yes. Power output is sofware-controlled to save battery (RGB LEDs draw up to 1 mA each when off).

• Does the magnetic USB-C adpater work with both variants?
  Yes. The switch does not collide with the magnet adapter.

The Puchi-BLE is heavily based on the open source project nRFMicro from Joric.
For each Puchi-BLE sold, a small amount is donated to the creator.

Controller comparison

Pinout