Compatible Hardware
Rabbit GRBL is designed to run on ESP32-based hardware platforms, offering high performance, flexibility, and multi-axis support. Choosing the correct hardware is important to ensure stable operation, proper I/O availability, and reliable CNC control.
This section provides guidance on compatible development boards and hardware platforms that can be used with Rabbit GRBL. While many ESP32 boards follow similar designs, not all variants are equally suitable for CNC applications, so careful selection is recommended.
Rabbit GRBL runs on the ESP32 platform. Espressif provides the ESP32 as a standalone chip, as a module, and as a complete development board. In most cases, the recommended option is to use an ESP32 development board, as it already includes USB connectivity, voltage regulation, and the required supporting components for easy programming and communication.
The image shows the ESP32-DevKitC-32D development board, a widely used ESP32-based module suitable for running Rabbit GRBL.
Commonly used and tested development boards include:
- ESP32 DevKit
- NodeMCU-32S
- DOIT ESP32 DEVKIT
- ESPduino 32
There are many ESP32 development board variations available on the market. While most follow the standard pinout, some versions may differ in GPIO availability, USB-to-Serial chips, or voltage regulator quality. It is recommended to verify the board specifications and ensure compatibility before use with Rabbit GRBL.
- Manufacturer: SourceRabbit
- Website: https://www.sourcerabbit.com
The Rabbit Board 4-Axis is a purpose-built CNC motion controller designed around the ESP32 architecture, engineered for stable and reliable operation inside real CNC control boxes.
The board integrates protected power input circuitry with reverse polarity protection and filtering capacitors to ensure clean and stable DC operation. Carefully designed voltage regulation and decoupling provide reliable logic supply rails, reducing the impact of electrical noise generated by motor drivers and switching power supplies.
Field inputs such as limit switches and probe are opto-isolated, protecting the controller from voltage spikes and interference. A dedicated programming and reset circuit ensures safe firmware flashing and predictable startup behavior.
The PCB layout follows CNC best practices, separating power and signal sections and maintaining clean grounding for improved stability and long-term reliability.
The Protoneer CNC Shield v3.0 can be used together with the ESPDuino-32 board when running Rabbit GRBL firmware. Rabbit GRBL includes a dedicated pin configuration for this hardware combination, allowing direct compatibility with the standard layout of the Protoneer CNC Shield v3.0.
By using the corresponding pin definition file inside the Rabbit GRBL source code, the shield operates according to its standard STEP/DIR architecture and supports limit switches, probe input and spindle control as defined by the board layout.
⚠️ NoticeIn order to make it work you need to modify the Protoneer V3.0 CNC Shield and remove the end stop resistor R1, as this causes the ESP32 to enter an endless reset loop which prevents it from booting up. Simply removing the resistor fixes this issue.