How do you detect a sequence of "1101" arriving serially
from a signal line?

Answers were Sorted based on User's Feedback



How do you detect a sequence of "1101" arriving serially from a signal line? ..

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

How do you detect a sequence of "1101" arriving serially from a signal line? ..

Answer / guest

from a state machine of four states

Is This Answer Correct ?    9 Yes 0 No

How do you detect a sequence of "1101" arriving serially from a signal line? ..

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

How do you detect a sequence of "1101" arriving serially from a signal line? ..

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

How do you detect a sequence of "1101" arriving serially from a signal line? ..

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

How do you detect a sequence of "1101" arriving serially from a signal line? ..

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

How do you detect a sequence of "1101" arriving serially from a signal line? ..

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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