Open loop motion control
12.6 Subroutines created by the Motion wizard for the Axis of Motion
S7-200 SMART
System Manual, V2.3, 07/2017, A5E03822230-AF
635
12.6.14
AXISx_ABSPOS subroutine
Table 12- 30 AXISx_ABSPOS
LAD / FBD
STL
Description
CALL AXISx_ABSPOS,
START, RDY, INP,
Res, Drive, Port,
Done, Error, D_Pos
The AXISx_ABSPOS subroutine reads the absolute position from cer-
tain Siemens servo drives, such as the V90. You read the absolute
position value in order to update the current position value in the Axis of
Motion. This capability is supported when using a SINAMICS V90 servo
drive combined with a SIMOTICS-1FL6 servo motor that has an abso-
lute encoder installed.
Table 12- 31 Parameters for the AXISx_ABSPOS subroutine
Inputs/Outputs
Data type
Operands
START
BOOL
I, Q, V, M, SM, S, T, C, L, Power Flow
RDY, INP
BOOL
I, Q, V, M, SM, S, T, C, L
Res
DINT
ID, QD, VD, MD, SMD, SD, LD, AC, *VD, *AC, *LD, Con-
stant
Drive
BYTE
IB, QB, VB, MB, SMB, SB, LB, AC, *VD, *AC, *LD, Con-
stant
Port
BYTE
IB, QB, VB, MB, SMB, SB, LB, AC, *VD, *AC, *LD, Con-
stant
Done
BOOL
I, Q, V, M, SM, S, T, C, L
Error
BYTE
IB, QB, VB, MB, SMB, SB, LB, AC, *VD, *AC, *LD
D_Pos
REAL
ID, QD, VD, MD, SMD, SD, LD, AC, *VD, *AC, *LD
Turn on the EN bit to enable the subroutine. Ensure that the EN bit stays on until the DONE
bit signals that the execution of the subroutine has completed.
Turn on the START parameter to obtain the current absolute position from the specified
drive. To ensure that only one operation to read the current position is performed, use an
edge detection element to pulse the START parameter on.
The RDY parameter indicates the readiness state of the servo drive, which is typically
provided by a digital output signal from the drive. This subroutine will read the absolute
position from the drive only if this parameter is on.
The INP parameter indicates the standstill state of the motor, which is typically provided by a
digital output signal from the drive. This subroutine will read the absolute position from the
drive only if this parameter is on.