How do you detect a sequence of "1101" arriving serially
from a signal line?
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Answer / amit malik
PS I/P NS O/P
S0 0 S0 0
S0 1 S1 0
S1 0 S0 0
S1 1 S2 0
S2 0 S3 0
S2 1 S2 0
S3 0 S0 0
S3 1 S1 1
| Is This Answer Correct ? | 27 Yes | 0 No |
Answer / virag
Use 4 flip-flops
Tap output from all 4 , connect the second bit to an
inverter and AND all the outputs .
When the output of AND gate is 1. the sequence is detected
| Is This Answer Correct ? | 8 Yes | 3 No |
Answer / govind vijayakumar
Just put a SIPO (Serial In Paralle Out)Network at the
output, followed by a gate network.
4 parallel outputs from the SIPO are taken and the signal
lines whose output is supposed to be one are fed to a 3
input and gate. The 0 output is fed to a not gate and the
output of both the gates are anded together. If this
sequence comes then output will be one, otherwise 0.
| Is This Answer Correct ? | 5 Yes | 5 No |
Answer / guest
PS I/P NS O/P
S0 0 S0 0
S0 1 S1 0
S1 0 S0 0
S1 1 S2 0
S2 0 S3 0
S2 1 S1 0
S3 0 S0 0
S3 1 S1 1
when s2=1 it should go to s1... otherwise it will not detect
the sequence like "...11101..."
| Is This Answer Correct ? | 3 Yes | 3 No |
Answer / genesys
Answer 2 is not correct. It should be :
PS I/P NS O/P
S0 0 S0 0
S0 1 S1 0
S1 0 S0 0
S1 1 S2 0
S2 0 S3 0
S2 1 S0 0
S3 0 S0 0
S3 1 S1 1
where: PS - previous state of the state machine; i/p - input
to the state machine; NS - next state of the state machine;
O/P - output from the state machine
| Is This Answer Correct ? | 8 Yes | 9 No |
Answer / ankush
Sorry, I don't understand the answers here clearly. Can
anyone explain this more clearly
| Is This Answer Correct ? | 1 Yes | 3 No |
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