This driver HAT has been made to control up to 253 serial bus servos simultaneously. It uses the ESP32-WROOM-32 module for wired and wireless communication, making it ideal for robotics projects such as quadruped robots, hexapod walkers, and robotic arms.
It supports 9-25V wide voltage input and features multiple control demos. It connects to Raspberry Pi, providing power via a 5V buck regulator and communicates through the GPIO UART interface. The HAT also supports JSON command communication for advanced control and feedback.
Features
- Allows controlling up to 253 ST / RSBL series serial bus servos at the same time
- 9~25V wide voltage input (the input voltage and the servo voltage must be matched)
- Based on the ESP32-WROOM-32 module, supports wired and wireless communication
- Provides multiple control demos for different host controllers
- Supports controlling the serial bus servos directly via onboard USB Type-C port
- Supports connecting to Raspberry Pi, powering the Pi via integrated 5V buck regulator circuit and communicating through GPIO UART interface, neat cable management
What's on Board

- ESP32 module
- DCDC 5V buck regulator
- UART control switch
- Reset button
-
BOOT button
For entering download mode
- Raspberry Pi 40PIN header
- ESP32 Type-C port
- Serial bus servo Type-C port
- XT60 connector
- 5.5×2.5 DC power jack
- Power supply screw terminal
- RS485 serial bus servo header
- TTL serial bus servo headers
Specifications
Controller |
ESP32-WROOM-32 |
Power Supply Port |
XT60 connector, 5.5 x 2.5 mm DC jack |
Power Supply |
9~25V (the input voltage and the servo voltage must be matched) |
Communication Interface |
UART, 2x USB Type-C port |
Wireless Communication |
2.4G WiFi |
Mounting Hole Diameter |
3 mm |
Mounting Hole Spacing |
58 x 49 mm |
PCB Size |
65 x 57 mm |
Connection Example - Raspberry Pi & Servo

Resources
Pinout

Package Contents
- 1x Bus Servo Driver HAT (A)
- 1x 2 x 20-pin header
- 1x USB-A to USB-C cable
- 1x Screws pack