Table of Contents
Advertisement
S5-95F
Depassivation Routine
Note
Call FB255 only in the cyclic program (OB1). Generate an independent routine for
depassivation in your control program. In this routine, you make sure that the system
cannot assume any impermissible statuses during depassivation of the I/Os. Special
attention should be paid to the statuses of the digital outputs.
Special Characteristics of Depassivation
•
Please note that all failsafe I/Os are tested when you call up FB255 (not only the I/Os with the
signal group to be depassivated).
•
Calling FB255 is permissible only if FB252 is not active with an I/O test (DI, DQ, interrupt DI
or counter test). An active test can be interrogated at the PAFE output parameter (PAFE =
D0
).
H
•
Depassivation can be accelerated by multiple calling of FB255.
•
FB255 does not recognize a discrepancy present at a DI during depassivation. In such a case,
the signal group is briefly depassivated and automatically repassivated after elapse of the
discrepancy time.
Messages in the PAFE Byte
During the depassivation, the PAFE byte is D0
depassivation, the PAFE parameter is 00
signal group during depassivation, then the PAFE byte is 31
Example for Calling FB255
OB1
:
: JU FB 255
NAME: AGF: DEPA
AUFT: KY 0,0
DEPA: I 1.0
PAFE: FY100
EWA 4NEB 812 6210-02
. If the function block FB255 recognizes an error in the
H
STL
Blocks and Their Functions
or E0
. After successful completion of
H
H
.
H
Explanation
Call depassivation block
Job: Acknowledge error message
Trigger depassivation with edge at I 1.0
Reserve FY100 for PAFE
9-23
Advertisement
Table of Contents
