Functional description
powerSTEP01
7.7
Motor control commands
The powerSTEP01 can accept different types of commands:
•
•
•
•
constant speed commands (Run, GoUntil, ReleaseSW)
absolute positioning commands (GoTo, GoTo_DIR, GoHome, GoMark)
motion commands (Move)
stop commands (SoftStop, HardStop, SoftHiz, HardHiz).
For detailed command descriptions refer to Section 11.2.
7.7.1
Constant speed commands
A constant speed command produces a motion in order to reach and maintain a user-
defined target speed starting from the programmed minimum speed (set in the MIN_SPEED
register) and with the programmed acceleration/deceleration value (set in the ACC and DEC
registers). A new constant speed command can be requested anytime.
Figure 9. Constant speed command examples
Speed
(step frequency)
SPD3
Run(SPD4,BW)
SPD1
SPD2
Run(SPD2,FW)
Run(SPD3,FW)
Minimum
speed
Minimum
time
speed
Run(SPD1,FW)
SPD4
AM12856v1
7.7.2
Positioning commands
An absolute positioning command produces a motion in order to reach a user-defined
position that is sent to the device together with the command. The position can be reached
performing the minimum path (minimum physical distance) or forcing a direction (see
Figure 10).
Performed motor motion is compliant to programmed speed profile boundaries
(acceleration, deceleration, minimum and maximum speed).
Note that with some speed profiles or positioning commands, the deceleration phase can
start before the maximum speed is reached.
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