The Makerbase MKS DLC V2.1 is a high-performance control board designed for desktop CNC machines and laser engravers. It is powered by an ATmega328P microcontroller and runs GRBL-compatible firmware. Official Manual & Documentation Links
The official manual and hardware documentation for the Makerbase MKS DLC v2.1 (and its modern successor, the makerbase mks dlc v21 manual link
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Using the manual, verify these five points: The Makerbase MKS DLC V2