IDEC FL1E SmartRelay - Manual (Page 222)

IDEC SmartRelay functions
208 IDEC SmartRelay Manual 
4.4.25 Shift register
Short description
You can use the shift register function to read the value of an
input and to shift its bits left or right. The output value
corresponds with the configured shift register bit. The
shifting direction can be changed at a special input.
Functional description
The function reads the value at input In with a positive edge
(0 to 1 transition) at input Trg (Trigger).
This value is applied to shift register bit S1 or S8, depending
on the shifting direction:
• Shift up: The value at input In is set at S1; the previous
value at S1 is shifted to S2; the previous value at S2 is
shifted to S3 etc.
• Shift down: The value at input In is set at S8; the previous
value at S8 is shifted to S7; the previous value at S7 is
shifted to S6 etc.
Output Q returns the value of the configured shift register bit.
If retentivity is disabled, the shift function restarts at S1 or S8
after a power failure. When enabled, retentivity always
applies to all shift register bits.
Note
The special function shift register can be used only once in the cir-
cuit program.
Symbol in IDEC
SmartRelay
Wiring Description
Input In Input read at the start of the function.
Input Trg A positive edge (0 to 1 transition) at
input Trg (Trigger) starts the special
function. 1 to 0 transitions are
irrelevant.
Input Dir The signal at input Dir determines the
shifting direction for the shift register
bits S1...S8:
Dir = 0: Shift up (S1 >> S8)
Dir = 1: Shift down (S8 >> S1)
Parameter Shift register bit that determines the
value at output Q.
Possible settings: S1 ... S8
Retentivity: 
/ = No retentivity 
R = The status is retentive.
Output Q The output value corresponds with the
configured shift register bit.