Technical data

Updating the input and output bytes of the global I/Os
The times at which the CP 5430 TF/CP 5431 FMS updates the
GP bytes
to be transmitted
are either
➣
FREE
mode: decided by the CP (the STEP 5 control program has no
influence) or
➣
CYCLE-SYNCHRONIZED
mode: decided by the control program using
a send handling block call with job number 210.
The times at which the CP 5430 TF/CP 5431 FMS transfers the
received
GP bytes
to the CPU input area are also either
➣
FREE
mode: decided by the CP (or influenced by the STEP 5 control
program) or
➣
CYCLE-SYNCHRONIZED
mode: decided by the control program using
a RECEIVE handling block call with job number 211.
Consistency of the input and output bytes of the GP
➣
FREE
mode: guaranteed consistency of
one
byte.
➣
CYCLE-SYNCHRONIZED
mode: guaranteed consistency over the
whole area.
Special features
➣
CYCLE-SYNCHRONIZED
mode: when a GP station fails, the input
bytes assigned to this station are reset on the other stations (to the
value 0). Notes on the calculation of this "switch off time" can be found
in the appendix of this manual.
If the PLC changes from the RUN to the STOP mode, its GP output bytes
are reset (to the value 0). Since the CP 5430 TF/CP 5431 FMS registers
this change, each of these bytes which previously had a value other than
"0" is transmitted with the value "0".
Communication with Global I/Os B8976060/01
Volume 1 9 - 6