Technical data

In the PLC program, the control program changes the output byte to be
transmitted (PY 7).
In the CP cycle, the CP checks all (GP) output bytes for changes (new/old
comparison) and transmits only the GP bytes whose values have changed
since the last comparison.
Result
: the CP 5430 TF/CP 5431 FMS only sends a GP byte when its
value has changed between two consecutive "new/old" comparisons.
The value of the GP byte at the time of the new/old comparison is decisive.
If, in the meantime, a bit has changed its value more than once, but has
returned to its original value when the next comparison is made, these
changes are not recognized. Information about calculating the "reaction
times" of the global I/Os in the FREE mode can be found in the appendix of
this manual.
Communication with Global I/Os B8976060/01
Volume 1 9 - 8