Synchronous Flashcards
When does the output of a Mealy Machine change?
-any time as it couples through directly from the inputs
Why is a state table used?
-to ensure all possible operating scenarios are considered
When does the output of a Moore Machine change?
-only changes with a clock transition
In a mealy diagram where are the input and output conditions shown?
-On the transitions between states
In a moore diagram where are the input and output conditions shown?
- Input conditions are included on the transitions between states
- output conditions within the states
Each input to sequential machine is called what?
-a primary state variable
Each isolated memory element in a feedback path of a sequential machine is known as what?
-a secondary state variable
What is the total state?
primary state variables and the secondary state variables
In a mealy machine what is the output related to?
the total state
In a moore machine what is the output related to?
the internal state only
what are the pros and cons of using relay logic?
PROS -great isolation -good overload capacity -fail safe CONS -slow -mechanically limited no. of operations
Draw a RS flip flip transition table
S R Q(n) 0 0 Q(n) 0 1 0 1 0 1 1 1 not defined
Draw a D flip flip transition table
D Q(n) Q(n+1) 0 0 0 0 1 0 1 0 1 1 1 1
Draw a T flip flip transition table
D Q(n) Q(n+1) 0 0 0 0 1 1 1 0 1 1 1 0
Draw a JK flip flip transition table
J K Q(n) 0 0 Q(n) 0 1 0 1 0 1 1 1 Q(n)
What are the values of g1 and g2 for a D type?
D D
What are the values of g1 and g2 for a T type?
T(bar) T
What are the values of g1 and g2 for a JK type?
K(bar) J
What are the values of g1 and g2 for a RS type?
(S+R(bar)) S(n)
How do you word out how many SSV’s you need?
n=log2(r) where r is the number of states in the state diagram
How do you work out how many unallocated states there are?
2^n-r
How does the number of inputs effect the Moore Model?
2^(inputs) transitions from each states
