# Score board Increment and Decrement

#### ganny

Joined Feb 7, 2018
35
Hi everyone! I need your help in my project. We were asked to make a score board that can inrement 1, 2 and 3. Also it can decrement 1. I already did the bcd to seven segment decoder using only logic gates. My problem is after 9 it doesnt go back to zero. Could you help me about this. Only logic gates can be used.

#### dl324

Joined Mar 30, 2015
13,519
Welcome to AAC!

If this project is school work, it belongs in the Homework Help forum where members won't be tempted to just give you answers.
We were asked to make a score board that can inrement 1, 2 and 3. Also it can decrement 1..
Can you post the complete text of the problem? It's unclear if the counter should increment by 1, 2 (i.e. 0, 2, 4, ...), or 3 (i.e. 0, 3, 6, ...); or you're giving us the expected count sequence.
Only logic gates can be used.
Are you supposed to use logic gates to create the flip flops?
My problem is after 9 it doesnt go back to zero.
Post the schematic of what you have so far. Without one, we have no idea why your counter doesn't go from 9 to 0.

#### ganny

Joined Feb 7, 2018
35
Welcome to AAC!

If this project is school work, it belongs in the Homework Help forum where members won't be tempted to just give you answers.

Can you post the complete text of the problem? It's unclear if the counter should increment by 1, 2 (i.e. 0, 2, 4, ...), or 3 (i.e. 0, 3, 6, ...); or you're giving us the expected count sequence.

Are you supposed to use logic gates to create the flip flops?

Post the schematic of what you have so far. Without one, we have no idea why your counter doesn't go from 9 to 0.

#### ganny

Joined Feb 7, 2018
35
It should add 1, 2 or 3 not in the series. ex. if it display 4 you push the button for 2 increment it will be 6 also if you push the button increment of 3 it will display 9. And Yes only logic gates are required for ex. if we used flipflop it should be in logic gates form. By the way it is from 0-999

#### ganny

Joined Feb 7, 2018
35
Here is the schematic

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#### WBahn

Joined Mar 31, 2012
26,398
MOD NOTE: Moved to Homework Help.

#### dl324

Joined Mar 30, 2015
13,519
Here is the schematic
Post the complete text of the problem and give us a more clearly focused picture (e.g. a screen capture). Neatness counts. In addition to making it easier for someone else to read, it makes it easier for you to find any mistakes.

While you're at it, post your truth table and Kmaps and describe how you approached your solution. Also explain how you plan to extend the circuit to 3 digits.