Constant velocity and exact stop mode are settings to control the type of motion performed by the machine. Constant velecity means exactly what it says, it seemlessly issues movement commands and the machine maintains a constant speed dictated by the feed setting. Through all moves regardless of the direction. Exact stop mode will stop the machine on every block of code to ascertain that the move was carried out correctly. Reasons for using this would be a machine with low acceleration or being overdriven allowing one axis at a corner to take off before the other has completed it's traverse thereby rounding the corner rather than executing a move that produces a sharp corner.
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