little help on designing Mealy machine

EDAboard.com Forum Index -> Electronic Elementary Questions -> little help on designing Mealy machine

Author

Message

david90

Joined: 05 May 2004
Posts: 384
Helped: 1

10 May 2005 6:11 little help on designing Mealy machine

I'm given a state diagram and i'm suppose to only use JK FFs (no gates) and an EPROM to implement the state diagram. How do I do this?

Google
AdSense
Google Adsense

10 May 2005 6:11 Ads

Jack// ani

Joined: 02 Dec 2004
Posts: 488
Helped: 25

10 May 2005 9:14 little help on designing Mealy machine

You have to convert the state diagram into a tabular format.

VVV

Joined: 26 Nov 2004
Posts: 1584
Helped: 290

11 May 2005 0:24 Re: little help on designing Mealy machine

1. Establish the number of flip-flops, based on the number of states: #states <= 2^n, where n is the number of flip-flops.
2. Assign codes to the states in the diagram (combinations of Q outputs). Make sure you assign adjacent codes to adjacent states, or to states following tests of asynchronous signals.
3. Determine the required functions for each state, for each J and K input, based on the JK ff equation and the code of the next state.
4. The flip-flops Q outputs will be connected to addresses on the EPROM. Other addresses will go to the signals that need to be tested by you state-machine. The outputs of the EPROM are fed to the JK inputs of the flip-flops.

So now you see how it goes. In a certain state, the EPROM outputs the required J-K signals for the circuit to go to the next state when clocked. From that you know the contents of the EPROM.

VVV