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Why is s/r 1 considered an invalid input in an SR flip-flop?
S=1, R=1 is state forbidden in SR flip flop. The flip flop does not get damaged in forbidden state (S=R=1). It is called forbidden because there is no definitive gurantee of a fixed output.
What is the forbidden condition?
A forbidden state in this case means that the output is non deterministic, i.e. unknown. An unknown state is typically drawn as two parallel lines (meaning it could be at either level). Here are the various states, I’ve used a NAND based latch and inverted the inputs or ease of understanding.
When S 1 and r 0 the output state of the RS flip-flop is?
one of the input of the first NOR gate, now both the inputs of first NOR gate are at logic 0 so the output Q turns high i.e. at logic 1 as shown in the figure 3. Therefore it can clearly be depicted that when S=1 and R=0 it SETs the Latch.
What is an S-R flip?
S-R flip-flop stands for SET-RESET flip-flops. The SET-RESET flip-flop consists of two NOR gates and also two NAND gates. These flip-flops are also called S-R Latch. The design of these flip flops also includes two inputs, called the SET [S] and RESET [R]. There are also two outputs, Q and Q’.
What is the forbidden state of an SR flip flop?
Anyone who has implemented the simple SR flipflop in lab would have noticed that the flipflop doesnt essentially get damaged in forbidden state (S=R=1). It is called forbidden because their is no definitive guarentee of a fixed output. The main advantage of JK over SR is removal of this forbidden state. Yes, it toggles the previous state 😉 .
What happens when s = Your = 1 when using SR flip flops?
When S = R = 1 and if click is HIGH (for clocked SR FF), the output of both NAND gate at the input side will become 0. Now logic 0 is at the input of both output NAND gates. We know if any one input of NAND gate is logic 0 , its output will try to become logic 1.
What happens if you set your and s to 1?
In the original question, it is written that: But if you set both R and S to 1 we have that Q = 0 and Q ¯ = 0 at the same time. This contradicts the relation Q = Q ¯ . In the real world one of the gates will reach the 1 state first and the result will be unpredictable. This is true theoretically.
Why is the JK flip flop called a universal flip-flop?
The high state is 1 called SET state and Low state is 0 called RESET state. JK flipflop is most versatile flipflop and most commonly used when descrete devices are used to implement arbitary state machine. JK flipflop gate configuration is shown here with refined version of RS flipflop.