Description of the function
The function reads the value of input In with a positive edge (0 to 1 transition) at input Trg (Trigger).
This value is written to shift register bits S1 or S8, depending on the set shift direction:
Shift up: S1 accepts the value of input In; the previous value of S1 is shifted to S2, S2 is shifted to S3, etc.
Shift down: S8 accepts the value of input In; the previous value of S8 is shifted to S7, S7 is shifted to S6, etc.
Q outputs the value of the configured shift register bits.
If retentivity is not enabled, the shift function restarts at S1 or S8 after a power failure.
Note
The special function shift register can be used only once in the circuit program.