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About Rabbit GRBL

Rabbit GRBL is a modern, extended implementation of the original GRBL firmware, designed to run natively on the ESP32 platform. It is 100% compatible with standard GRBL, meaning all GRBL senders, G-code workflows, macros, and automation tools function exactly as expected without any modifications.

Built for the ESP32's higher processing power, Rabbit GRBL provides:

• Full GRBL v1.1 compatibility
  Every $ system command, real-time command, G-code mode, and status report format follows the official GRBL v1.1 specification.

• 6-Axis Motion Support
  Unlike classic GRBL (limited to 3 axes), Rabbit GRBL can control X, Y, Z, A, B, and C axes, enabling robotics, multi-axis CNC routers, pick-and-place systems, and automated mechanisms.

• High Step Rate Performance
  Capable of generating up to 120 kHz step rates, ensuring smooth motion even at high speeds, with high-resolution microstepping drivers.

• Enhanced performance on the ESP32
  The faster CPU, additional timers, and expanded I/O capabilities allow smoother motion control, faster planner execution, and more accurate real-time response.

• Reliable and deterministic reporting
  Always transmits MPos and periodically transmits WCO, enabling precise work-position reconstruction externally.

• Extended I/O and safety features
  More limit switch inputs, improved probe handling, safety-door logic, coolant outputs, and auxiliary control signals.

• Low-latency real-time behavior
  Feed hold, cycle start, overrides, and emergency control react within milliseconds due to the ESP32 interrupt system.

Rabbit GRBL preserves the simplicity and predictability of classic GRBL while taking full advantage of the ESP32, making it ideal for CNC machines, robots, plotters, and custom motion systems that need the speed and flexibility of a modern microcontroller.