"A M-R flip-flop behaves as follows:
If MR = 00, the flip-flop does not change state.
If MR = 10, the flip-flop is reset; i.e. Q=0.
If MR= 11, the flip-flop changes state.The input combination
MR = 01 is not allowed.
Give the next state equation for this flip flop"


I have no idea how to solve this, could anyone provide any hints / clarifications that might help me out?

 

Is this a "UV" flip flop or a "M-R" flip flop?

Look at the next state equations for a JK flip flop. The idea is very similar.

 

Is this a "UV" flip flop or a "M-R" flip flop?

Look at the next state equations for a JK flip flop. The idea is very similar.

It's an M-R flip flop, I apologize that was a typo. I have worked out a table for the solution and I think I may have gotten it:


x's are labeled as don't cares

M | R| Q | Q(+)
x 0 0 0
------ 0 1
1 x 1 0
0 0 1 1

when Q and Q(+) are both set to zero, this satisfies the condition in which MR = 00 and when MR = 10, since Q and Q(+) does not change state, and it also "resets" to 0, so m could be either 1 or 0, or just labeled as a don't care. The case of 01 is ignored since it is not allowed. The conditions are reversed for when Q = 1 and Q(+) = 0, this means MR = 10 and also equal to 11 since the values compliment. At Q and Q(+) = 1, MR has to be equal to 00 since it does not change state...

is this correct?

 

I have no idea what the line in your table is that has all the hyphens.

Using TABLE tags might help.

You are talking about Q(+) as thought it is one of your inputs.

Your table doesn't cover the case where MR = 11 and Q = 0.

 

I have no idea what the line in your table is that has all the hyphens.

Using TABLE tags might help.

You are talking about Q(+) as thought it is one of your inputs.

Your table doesn't cover the case where MR = 11 and Q = 0.

the line with the hyphens I used to show that the case in which MR = 01 is not allowed in the problem. For a certain part, I was asked to fill out the corresponding characteristic table with the correct MR inputs, so I was given:

// MR are left blank for me to fill out

Q | Q(+) | M | R
0 | 0 | |
0 | 1 | |
1 | 0 | |
1 | 1 | |

I don't know how to use table tags.

Since I was given this specific table to fill out, I need to find the U and V inputs that satisfy these conditions, so for example M = 0 and R= 0, when Q is 1 and Q(+) is 1, since the state does not change from Q, to Q(+). Would my table be correct for these circumstances?

 

the line with the hyphens I used to show that the case in which MR = 01 is not allowed in the problem. For a certain part, I was asked to fill out the corresponding characteristic table with the correct MR inputs, so I was given:

// MR are left blank for me to fill out

Q | Q(+) | M | R
0 | 0 | |
0 | 1 | |
1 | 0 | |
1 | 1 | |

I don't know how to use table tags.

Since I was given this specific table to fill out, I need to find the U and V inputs that satisfy these conditions, so for example M = 0 and R= 0, when Q is 1 and Q(+) is 1, since the state does not change from Q, to Q(+). Would my table be correct for these circumstances?

What are these 'U' and 'V' inputs that you keep talking about?

 

What are these 'U' and 'V' inputs that you keep talking about?

Nevermind! I solved it earlier today. Thank you for the help