Siemens SIMATIC S7-200 System Manual page 297

POSx_CLR Instruction
The POSx_CLR instruction (Pulse the CLR Output)
commands the Position module to generate a 50-ms pulse
on the CLR output.
Turning on the EN bit enables the instruction. Ensure that
the EN bit stays on until the Done bit signals that the
execution of the instruction has completed.
Turning on the START parameter sends a CLR command to
the Position module. For each scan when the START
parameter is on and the Position module is not currently
busy, the instruction sends a CLR command to the Position
module. To ensure that only one command is sent, use an
edge detection element to pulse the START parameter on.
The Done parameter turns on when the module completes
this instruction.
The Error parameter contains the result of this instruction.
See Table 9-20 for definitions of the error codes.
Table 9-18 Parameters for the POSx_CLR Instruction
Inputs/Outputs
START
Done
Error
Open Loop Motion Control with the S7-200
Data Type Operands
BOOL I, Q, V, M, SM, S, T, C, L, Power Flow
BOOL I, Q, V, M, SM, S, T, C, L
BYTE IB, QB, VB, MB, SMB, SB, LB, AC, *VD, *AC, *LD
Chapter 9
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