Siemens SINUMERIK 840Di sl Programming Manual page 289

There is no difference between DC and AC dimensioning. In both cases, rotation continues
in the direction selected by M3/M4 until the absolute end position is reached. With ACN and
ACP, deceleration takes place if necessary, and the appropriate approach direction is
followed. With IC, the spindle rotates additionally to the specified value starting at the current
spindle position.
When M3 or M4 is active, the spindle decelerates if necessary, and accelerates in the
programmed direction of rotation.
Position a spindle from standstill (M5)
The exact programmed distance is traversed from standstill (M5).
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
Feedrate Control and Spindle Motion
7.4 Positioning spindles (SPOS, M19 and SPOSA, WAITS)
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