SEQUENTIAL ELEMENTS (FLIP-FLOPS)
DD FLIP-FLOP
Captures input D on clock rising edge.
| D | CLK โ | Q |
|---|
| 0 | โ | 0 |
| 1 | โ | 1 |
| X | โ | Q (hold) |
TT FLIP-FLOP (TOGGLE)
Toggles Q when T=1, holds when T=0.
| T | CLK โ | Q_next |
|---|
| 0 | โ | Q (hold) |
| 1 | โ | Qฬ (toggle) |
SRSR FLIP-FLOP (SET-RESET)
S=Set, R=Reset. S=1 sets Q=1, R=1 sets Q=0.
| S | R | CLK โ | Q_next |
|---|
| 0 | 0 | โ | Q (hold) |
| 0 | 1 | โ | 0 (reset) |
| 1 | 0 | โ | 1 (set) |
| 1 | 1 | โ | 1 (S priority) |
JKJK FLIP-FLOP
Versatile FF: J=Set, K=Reset, J=K=1 toggles.
| J | K | CLK โ | Q_next |
|---|
| 0 | 0 | โ | Q (hold) |
| 0 | 1 | โ | 0 (reset) |
| 1 | 0 | โ | 1 (set) |
| 1 | 1 | โ | Qฬ (toggle) |