SR Set-Reset Flip Flop

SR  Set-Reset Flip Flop 







Parameter  Data Type      Memory Area       Description
<address>   BOOL      I, Q, M, L, D           Set or reset bit
     S           BOOL     I, Q, M, L, D       Enable set instruction
     R           BOOL     I, Q, M, L, D       Enable reset instruction
     Q           BOOL     I, Q, M, L, D      Signal state of <address>
Description 
SR (Set-Reset Flip Flop) is set if the signal state is "1" at the S input, and "0" at the R input. Otherwise,
if the signal state is "0" at the S input and "1" at the R input, the flip flop is reset. If the RLO is "1" at
both inputs, the order is of primary importance. The SR flip flop executes first the set instruction then
the reset instruction at the specified <address>, so that this address remains reset for the remainder
of program scanning.
The S (Set) and R (Reset) instructions are executed only when the RLO is "1". RLO "0" has no effect
on these instructions and the address specified in the instruction remains unchanged.
MCR (Master Control Relay) dependency
MCR dependency is activated only if a SR flip flop is placed inside an active MCR zone. Within an
activated MCR zone, if the MCR is on; the addressed bit is set to "1" or reset to "0" as described
above. If the MCR is off, the current state of the specified address remains unchanged regardless of
input states.

If the signal state is "1" at input I0.0 and "0" at I0.1, memory bit M0.0 is set and output Q4.0 is "1".
Otherwise, if the signal state at input I0.0 is "0" and at I0.1 is "1", memory bit M0.0 is reset and output
Q4.0 is "0". If both signal states are "0", nothing is changed. If both signal states are "1", the reset
instruction dominates because of the order; M0.0 is reset and Q4.0 is "0".

If the example is within an activated MCR zone:
When MCR is on, Q4.0 is set or reset as described above.
When MCR is off, Q4.0 is left unchanged regardless of input states.

!--RELATED-POSTS-STARTS-->