Whenever I see the "flip-flop" discussed on here, I look out for a complete specification of what actually is required.
In particular, the majority of these "solutions" do indeed work as flip-flops under normal circumstances, but rarely is it mentioned what should happen if the processor goes through a power-cycle.
I can only speak for A-B processors, I don't know how others behave, but many of the so-called "solutions" posted will not retain the state through a power-cycle, or indeed a mode change Run-Program-Run.
IMHO a proper "flip-flop" should always retain its state, and in applications that require it to reset, that should be a programmed action on start-up.
For A-B I personally prefer the Counter solution, which is retentive, and provide a separate RES of it if required using the "First-Scan" status.
