Handshake procedure

The handshake procedure is used for some variables to transport information. A value, e.g. logical "1" (switching request), is written to a variable by the manual operation. This value is set back to a logical "0" after processing by the function block:

0 → 1: Switching request by manual operation

1 → 0: Switching request was read

The reset only describes that the value has been read. It does not mean that this value has also had an influence. The state-describing variable is used to show whether a value has influenced an output of the function block.