How Can a D-Type Flip Flop Handle Simultaneous High Inputs?

[transgalactic]

http://img329.imageshack.us/my.php?image=39501432oa1.jpg

if one of them was 0 then no problem because the other wire value doesn't matter
but here we have both 1
if i look on one of the NANDs gates we have one input of 1
and the other input value is unknown because it comes from the resolt of the other gate
which has the same problem

how to solve it??

 

[ranger]

When SET = RESET = 1, there are two likely outputs of our RS NAND latch. We can have Q = 0 and Q(not) = 1. In this case, the input to the lower NAND gate is 0 and 1, which gives Q(not) = 1. The inputs to the first NAND are both 1 which makes Q = 0.

The second possibility is to have Q = 1 and Q(not) = 0. The same analysis used above can be applied for this situation.

So which situation occurs first? This depends on what has occurred previously at the inputs.

 

[piercas]

Based on the image provided, it appears that the flip flop in question is a D-type flip flop. In this type of flip flop, the output value is determined by the input value at the moment the clock signal changes. In this case, if both inputs are 1, the output will depend on the previous state of the flip flop, which is unknown. This can lead to unpredictable behavior.

To solve this issue, one possible solution would be to add a third input to the flip flop, known as the asynchronous reset input. This input allows the flip flop to be reset to a known state, regardless of the clock signal. By tying this input to a specific value, the flip flop can be forced into a known state and eliminate the issue of both inputs being 1.

Another solution could be to use a different type of flip flop, such as a JK flip flop, which has a more predictable behavior when both inputs are 1. Alternatively, the circuit design could be modified to avoid this situation altogether, such as by using logic gates to control the input values or by using a different type of sequential logic circuit.

Ultimately, the best solution will depend on the specific requirements and constraints of the circuit in question. It is important for a scientist to carefully analyze the problem and consider all possible solutions before making a decision on how to solve it.