|Eingeführt:||2.0 Beta 1|
Each flip-flop stores a single bit of data, which is emitted through the Q output on the east side. Normally, the value can be controlled via the inputs to the west side. In particular, the value changes when the clock input, marked by a triangle on each flip-flop, rises from 0 to 1 (or otherwise as configured); on this rising edge, the value changes according to the table below.
|D Flip-Flop||T Flip-Flop||J-K Flip-Flop||S-R Flip-Flop|
Another way of describing the different behavior of the flip-flops is in English text.
D Flip-Flop: When the clock triggers, the value remembered by the flip-flop becomes the value of the D input (Data) at that instant.
T Flip-Flop: When the clock triggers, the value remembered by the flip-flop either toggles or remains the same depending on whether the T input (Toggle) is 1 or 0.
J-K Flip-Flop: When the clock triggers, the value remembered by the flip-flop toggles if the J and K inputs are both 1 and the value remains the same if both are 0; if they are different, then the value becomes 1 if the J (Jump) input is 1 and 0 if the K (Kill) input is 1.
S-R Flip-Flop: When the clock triggers, the value remembered by the flip-flop remains unchanged if R and S are both 0, becomes 0 if the R input (Reset) is 1, and becomes 1 if the S input (Set) is 1. The behavior in unspecified if both inputs are 1. (In Logisim, the value in the flip-flop remains unchanged.)
By default, the clock triggers on a rising edge — that is, when the clock input changes from 0 to 1. However, the Trigger attribute allows this to change to a falling edge (when the clock input changes from 1 to 0), a high level (for the duration that the clock input is 1), or a low level (for the duration that the clock input is 0). The level-trigger options are unavailable for the T and J-K flip-flops, because a flip-flop behaves unpredictably when told to toggle for an indeterminate amount of time.
rising edgeindicates that the flip-flop should update its value at the instant when the clock rises from 0 to 1. The
falling edgevalue indicates that it should update at the instant the clock falls from 1 to 0. The
high levelvalue indicates that the flip-flop should update continuously whenever the clock input is 1. And the
low levelvalue indicates that it should update continuously when the clock input is 0. Note that the latter two options are unavailable for T and J-K flip-flops.
Clicking a flip-flop using the Poke Tool toggles the bit stored in the flip-flop, unless the asynchronous set/reset inputs currently pin the flip-flop's value.
Allows the label associated with the component to be edited.
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