Editing Propositional formula (section)

==== Flip-flop memory ====
The next simplest case is the "set-reset" [[Flip-flop (electronics)|flip-flop]] shown below the once-flip. Given that r=0 & s=0 and q=0 at the outset, it is "set" (s=1) in a manner similar to the once-flip. It however has a provision to "reset" q=0 when "r"=1. And additional complication occurs if both set=1 and reset=1. In this formula, the set=1 ''forces'' the output q=1 so when and if (s=0 & r=1) the flip-flop will be reset. Or, if (s=1 & r=0) the flip-flop will be set. In the abstract (ideal) instance in which s=1 ⇒ s=0 & r=1 ⇒ r=0 simultaneously, the formula q will be indeterminate (undecidable). Due to delays in "real" OR, AND and NOT the result will be unknown at the outset but thereafter predicable.

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|- style="font-size:9pt" align="center"
!  width="19.5" Height="12" | 
!  width="19.5" | 
!  width="19.5" | 
!  width="14.25" | 
!  width="14.25" | 
! style="background-color:#FDE9D9;font-weight:bold" width="14.25" | q
!  width="14.25" | 
!  width="14.25" | 
!  width="16.5" | 
!  width="14.25" | 
!  width="14.25" | 
!  width="14.25" | 
!  width="14.25" | 
!  width="14.25" | 
!  width="14.25" | 
!  width="23.25" | 
!  width="153" | 
|- style="font-size:9pt" align="center"
! style="font-weight:bold" Height="12" | p
! style="font-weight:bold" | s
! style="font-weight:bold" | r
! style="font-weight:bold" | (
! style="background-color:#FCFF7F;font-weight:bold" | s
! style="background-color:#FDE9D9;font-weight:bold" | &or;
! style="font-weight:bold" | (
! style="font-weight:bold" | p
! style="background-color:#DBE5F1;font-weight:bold" | &
! style="background-color:#EAF1DD;font-weight:bold" | ~
! style="font-weight:bold" | (
! style="background-color:#FCFF7F;font-weight:bold" | r
! style="font-weight:bold" | )
! style="font-weight:bold" | )
! style="font-weight:bold" | )
! style="background-color:#FDE9D9;font-weight:bold" |  = q
!  
|- style="font-size:9pt" align="center"
| Height="12" | 0
| 0
| 0
| 
| 0
|style="background-color:#FDE9D9" | 0
| 
| 0
|style="background-color:#DBE5F1" | 0
|style="background-color:#EAF1DD" | 1
| 
| 0
| 
| 
| 
|style="background-color:#FDE9D9" | 0
| state 0 with ( s=0 & r=0 )
|- style="font-size:9pt" align="center"
| Height="12" | 0
| 0
| 1
| 
| 0
|style="background-color:#FDE9D9" | 0
| 
| 0
|style="background-color:#DBE5F1" | 0
|style="background-color:#EAF1DD" | 0
| 
|style="background-color:#FCFF7F" | 1
| 
| 
| 
|style="background-color:#FDE9D9" | 0
| state 0 with ( s=0 & r=1 )
|- style="font-size:9pt" align="center"
|style="background-color:#D8D8D8" Height="12" | 0
|style="background-color:#D8D8D8" | 1
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 1
|style="background-color:red" | 1
|style="background-color:#D8D8D8" | 
|style="background-color:red" | 0
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 1
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | q & p inconsistent
|- style="font-size:9pt" align="center"
|style="background-color:#D8D8D8" Height="12" | 0
|style="background-color:#D8D8D8" | 1
|style="background-color:#D8D8D8" | 1
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 1
|style="background-color:red" | 1
|style="background-color:#D8D8D8" | 
|style="background-color:red" | 0
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 1
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | q & p inconsistent
|- style="font-size:9pt" align="center"
| Height="12" | 1
| 0
| 0
| 
| 0
|style="background-color:#FDE9D9" | 1
| 
| 1
|style="background-color:#DBE5F1" | 1
|style="background-color:#EAF1DD" | 1
| 
| 0
| 
| 
| 
|style="background-color:#FDE9D9" | 1
| state 1 with ( s=0 & r=0 )
|- style="font-size:9pt" align="center"
|style="background-color:#D8D8D8" Height="12" | 1
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 1
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 0
|style="background-color:red" | 0
|style="background-color:#D8D8D8" | 
|style="background-color:red" | 1
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 0
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 1
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | 
|style="background-color:#D8D8D8" | q & p inconsistent
|- style="font-size:9pt" align="center"
| Height="12" | 1
| 1
| 0
| 
|style="background-color:#FCFF7F" | 1
|style="background-color:#FDE9D9" | 1
| 
| 1
|style="background-color:#DBE5F1" | 1
|style="background-color:#EAF1DD" | 1
| 
| 0
| 
| 
| 
|style="background-color:#FDE9D9" | 1
| state 1 with ( s=1 & r=0 )
|- style="font-size:9pt" align="center"
|style="background-color:#F2F2F2" Height="12" | 1
|style="background-color:#F2F2F2" | 1
|style="background-color:#F2F2F2" | 1
|style="background-color:#F2F2F2" | 
|style="background-color:#FCFF7F" | 1
|style="background-color:#FDE9D9" | 1
|style="background-color:#F2F2F2" | 
|style="background-color:#F2F2F2" | 1
|style="background-color:#DBE5F1" | 0
|style="background-color:#EAF1DD" | 0
|style="background-color:#F2F2F2" | 
|style="background-color:#FCFF7F" | 1
|style="background-color:#F2F2F2" | 
|style="background-color:#F2F2F2" | 
|style="background-color:#F2F2F2" | 
|style="background-color:#FDE9D9" | 1
|style="background-color:#F2F2F2" | state 1 with s & r simultaneously 1
|}