User Manual

Motion control is easy
10.6 Operation of motion control for S7-1200
Easy Book
242 Manual, 03/2014, A5E02486774-AF
Table 10- 34 Condition codes for ERRORID and ERRORINFO
ERRORID
(W#16#...)
ERRORINFO
(W#16#...)
Description
0
0
Successful read of a parameter
8410
0028
Invalid parameter (incorrect length)
8410
0029
Invalid parameter (no TO-DB)
8410
0030
Invalid parameter (not readable)
8411
0032
Invalid parameter (wrong value)
TO parameters
The axis "MotionStatus" consists of four values. You will want to monitor changes in these
values, which can be read while the program is running:
Variable name
Data type
Readable through
MC_ReadParam
MotionStatus:
Structure
No
• Position
REAL Yes
• Velocity
REAL Yes
• Distance
REAL Yes
• TargetPosition
REAL Yes
10.6
Operation of motion control for S7-1200
10.6.1
CPU outputs used for motion control
The CPU provides four pulse output generators. Each pulse output generator provides one
pulse output and one direction output for controlling a stepper motor drive or a servo motor
drive with pulse interface. The pulse output provides the drive with the pulses required for
motor motion. The direction output controls the travel direction of the drive.
The PTO output generates a square wave output of variable frequency. Pulse generation is
controlled by configuration and execution information supplied through H/W configuration
and/or SFCs/SFBs.
Based upon the user’s selection while the CPU is in RUN mode, either the values stored in
the image register or the pulse generator outputs drive the digital outputs. In STOP mode,
the PTO generator does not control the outputs.
Onboard CPU outputs and outputs of a signal board can be used as pulse and direction
outputs. You select between onboard CPU outputs and outputs of the signal board during
device configuration under Pulse generators (PTO/PWM) on the "Properties" tab. Only PTO
(Pulse Train Output) applies to motion control.