This repository provides an Arduino-compatible board support package (BSP) for the Johnny552 development board, which uses the WCH CH552P microcontroller. It is based on ch55xduino but specifically configured for the Johnny552 pinout and hardware layout.

Johnny552 is a compact, USB-powered development board featuring:

• CH552P (8051-core USB microcontroller)
• Boot/user buttons
• Exposed GPIO, UART, PWM, ADC, and interrupt pins
• Onboard SK6812 RGB LED
• AHT21 sensor
• USB HID/MIDI/CDC capable

This BSP is not yet available via Boards Manager. To install manually:

1. Clone this repository into your Arduino hardware directory:

mkdir -p ~/Arduino/hardware/johnny552
cd ~/Arduino/hardware/johnny552
git clone https://github.com/Johnny552/johnny552-arduino-bsp.git .

2. Restart the Arduino IDE.

3. Under Tools > Board, select Johnny552.

The Johnny552 comes with a USB bootloader pre-installed. To enter bootloader mode:

1. Hold the BOOT button
2. Connect the board to USB
3. Release the BOOT button

Then upload your sketch from the Arduino IDE.

For more detailed instructions, see the Arduino Installation Guide.

• Pin-out documentation can be found on: Johnny552 Project
• Hardware design: Johnny552 Project
• Arduino Installation Guide
• Johnny552 Documentation
• Hardware Documentation
• Bootloader Web Tool - Flash firmware directly from your browser

• Based on ch55xduino by Deqing Sun
• The Johnny552 team on Hackaday

The Johnny552 Arduino BSP software is licensed under the GNU Lesser General Public License v2.1.

Hardware designs are licensed under the GNU Lesser General Public License v2.1.

Documentation is licensed under the GNU Lesser General Public License v2.1.

This project is based on the CH55xduino project.