Hello,
Problem
I'm given an output sequence of an asynchronous circuit(attached). I have to design the circuit and provide exitation functions, transition table and total state table. Hazards must be avoided.
Question
To find excitation functions I need to make a flow table, then transition table. But thereis noinformation what happens when inputs are 01? Such values of inputs does not exist in the given sequence. I'm stuck.
Trial
1) I assumed that x and z0 are inputs, and z1 is an output. It is not specified in the task.
State table:
state x z0 z1
a 00 0
b 11 0
c 10 1
__________________
2) For total state table I assigned a=00, b=11, c=10 and an extra state d=01. I put don't care conditions for d:
xz0 (inputs)
###00# 01# 11 #10
_______________________
00 00,0 _,_ 11,0 10,0
_______________________
01 00,0 _,_ 11,0 10,0
_______________________
11 00,0 _,_ 11,0 10,0
_______________________
10 _,_ _,_ _,_ _,_
_______________________
next state, z1(output)
I feel this is incorrect, but can't guess what to do either.
Thanks a lot!
Problem
I'm given an output sequence of an asynchronous circuit(attached). I have to design the circuit and provide exitation functions, transition table and total state table. Hazards must be avoided.
Question
To find excitation functions I need to make a flow table, then transition table. But thereis noinformation what happens when inputs are 01? Such values of inputs does not exist in the given sequence. I'm stuck.
Trial
1) I assumed that x and z0 are inputs, and z1 is an output. It is not specified in the task.
State table:
state x z0 z1
a 00 0
b 11 0
c 10 1
__________________
2) For total state table I assigned a=00, b=11, c=10 and an extra state d=01. I put don't care conditions for d:
xz0 (inputs)
###00# 01# 11 #10
_______________________
00 00,0 _,_ 11,0 10,0
_______________________
01 00,0 _,_ 11,0 10,0
_______________________
11 00,0 _,_ 11,0 10,0
_______________________
10 _,_ _,_ _,_ _,_
_______________________
next state, z1(output)
I feel this is incorrect, but can't guess what to do either.
Thanks a lot!
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