Digital Logic - Making a State Machine with JK flip-flops

This is one of a series of videos where I cover concepts relating to digital electronics. In this video I talk about how to convert a state table into a functioning circuit that uses JK flip-flops.

[@taekwondotime]

I've been learning this material recently to prep for an engineering exam. The following might help others: 1. The first thing you need is your state table. (How to move from present state to next state.) You can derive the next state equations (called *"characteristic equations"* ) from that. 2. Once you have your state table, if you're designing with anything OTHER THAN D-flip flops, then you need to work out the *flip flop INPUT EQUATIONS* , because they will be different from your next state equations. The four rightmost columns in his state table are the flip flop input equations. FYI: The table he created at the top left of the board is called an *EXCITATION TABLE* , and it's NOT necessary to do these problems. Why? The table is FIXED because the behaviour of the underlying flip flop never changes. A JK flip flop behaves the same way all the time. Once you know it, that table will be in your brain automatically.

[@zither3416]

Thank you so much!!! Knowing that is called an excitation table is really helpful. Bless you~

[@felixbarrios2799]

I just want to grateful for the time that you spent doing this so useful work. I am actually designing a little circuit avoiding use microcontrolers and this class has been wonderfull to reach my goal, thank you very much :)

[@critterpower]

You are the best! Keep up the awesome work, this is the only video I've found that guides the viewer through a State Table with jk flip flop excitation. Keep on HAMing it!

[@aliciapavan9]

Thank you so much for this!! Helped me to understand what hours of lecture didn't.

[@muhammadnasihi2496]

great work dude ! Im currently takin electrical engineering. Your lecture helps me a lot! Thank you again. May God Bless you

[@taekwondotime]

*RE: K-maps (Karnaugh maps):* The K-maps are used to simplify boolean equations so that you reduce them to the minimum number of terms and literals. This is done to save money on circuitry and optimize the circuit so it runs as fast as possible. Every place where the function produces a "1", the K-map has a "1" in the corresponding box. There's no need to list the 0's. The "X" represents a "don't care" condition, which means it can take on the value of 0 or 1 -- whatever you need it to in order to help with the simplification. Simplification involves finding adjacent groups of 1's in the grid that are in powers of 2. Thus, you can circle two boxes, four boxes, eight boxes, etc. If a bigger grouping is available, you always take it.

[@kukaneswaranselvarajoo9377]

Did you make a mistake finding Jb and Kb?

[@KSITREVS]

I managed to understand the subject due to your vid! Thanks a bunch :)

[@py4735]

Really helpful!!! Did solve my questions, now I am confusing about how to make a recording like that lol

[@chrishadjipetris6059]

There's a mistake in this video, the expression should be In XNOR B, because before simplification it was In*B+'In*'B, meaning that both A and B should be the same (either 1, or 0)

[@paarik3157]

These videos are amazing! Helped me so much!

[@josepaul2000]

Thanks for the video! Do you reverse your videos?

[@rudytrevino5872]

Can this be done backwards? I have a circuit diagram of JK Flip flops and need to find the next state equation, table, & diagram.

[@omerfarukunal4203]

It was helpful thanks for the lesson

[@FelicianoMurillo]

I think there is a mistake on your k-maps finding your J_B and your K_B

[@briandillon2378]

The InB = InB(Notted) is an ExNor not an Exor and a Exnor is an Exor Notted

[@briandillon2378]

Should say the InB + InB(Notted) is an ExNor not an Exor - and an ExNor is an Exor(Notted)"

[@innocentokoloko]

​@@briandillon2378 A xor B'=AB''+A'B'=AB+A'B'

[@tilemachostsiapras3224]

realy helpfull !!!thanks

[@yodadback]

would this be a mealy model since the outputs are on the outside of the state?

[@primitzisgate7]

What if our state diagram has 3 bits to represent each state (A,B,C).Then at the karnaugh map i should use AB/CX for example?(x=input).And if there is a value at the karnaugh map eg 00/10 which it doesen't exist at the state table what do i put in that box at the karnaugh map? thanks :D

[@Rodion491]

thank you, very useful! But i have a question: InB+/In/b is the opposite of each other, why it cant be simplified to 1?

[@AntonioVerlotta]

Try to make the truth table and you will see that the output of the function is not always 1.

[@lleaves]

Very difficult to read the glass wall, unfortunately.

[@Exoepxoe]

they still use it after 10 years unfortunately

[@h.ibrahimakkus]

ANLAYAMIYOOOOOOOOOOOOOOOOOOOOOOOOOOOOOMMMM

[@mileyice13]

Thank you thank you thank you

[@TheNthPeterLEE]

could you teach me about dampers?

[@unswka2379]

Holly shit dude thanks a lot gg wp , 18/20

[@lprater11]

This video is very confusing.

[@haziqassiddiq7884]

bang rambut tukar kaler aah

[@philipokke]

those squeaking sounds :/

[@jl9285]

Better on glass than paper

[@mohamedshaat9922]

you can fly back home once you finish doing videos with these side burns

[@anishvarmapakalapati4670]

hello

[@pancekaradzov3885]

You missed SR flip flop in your videos...

[@randomuser5443]

Learning electrical engineering from a dude with a confederate barber

[@gentreshtani826]

Gosh, you did a very poor job at explaining this subject/topic. I watched it 5 times just to make sure that I'm not the problem. Geez.

[@xxxamuchixx]

he sucks

[@guaplei1]

squeaky squeak

[@HarjoteSingh]

Please shave off your side burns !!!! its sooo anoying

[@xxxamuchixx]

they mad ugly

[@yosibennaim4973]

I love those videos! jusr one thing - it's (InxorB)'