# Help with state table

Discussion in 'Homework Help' started by arcsky, Apr 17, 2009.

1. ### arcsky Thread Starter Member

Apr 17, 2009
12
0
Hello all,
I wonder if you guys maybe can help me out with this small problem,
http://hem.passagen.se/dmsn/design.jpg
The two lines in the state-table i dont understand how to fill it.
I doesn't understand how to think.

2. ### SawabyPlus Member

Feb 27, 2009
14
0
you may fill them the same way you've filled the other 2 rows.
starting from state (01) it moves to state (11) if a = '0' which means the first and last column.
it also moves to state (00) if a = '1' which is the 2nd and 3rd column.

same for state (10).

but i think there's a contradiction in state (11) transition conditions, where both conditions are active when a = '0' and b = '0', is there any kind of priority? check it out!

3. ### arcsky Thread Starter Member

Apr 17, 2009
12
0
Hi thanks for trying to help.
But that was wrong :/
Also i dont think two states can have same rows.

4. ### SawabyPlus Member

Feb 27, 2009
14
0
i don't understand what's wrong with my answer!
that would be the second row, and as shown it would be [ 11 | 00 | 00 | 11 ]

also fourth row would be [ 10 | 10 | 11 | 11 ].

Also i still believe the state diagram has some contradiction concerning transition conditions of state (11), unless some sort of priority applies, because if a and b both equal zero then both conditions are correct!

what's wrong with what i've said? can u clarify?

5. ### arcsky Thread Starter Member

Apr 17, 2009
12
0
Ah nice i think i understand your idea now on row 2 and 4.
But hmm the state (11) is wierd yes i have no idea why.
But i dont think teacher have made a wrong diagram.
I dont know more than all the info on the picture...
How would you think row for state (11) should be?

Is this maybe any important ?
"A simple sequential circuit with state diagramet as above to the left to be realized in a PLD circuit
(The first PAL circuit 16R4 that was introduced in 1978 would reach more than ...)"

Last edited: Apr 18, 2009