# How can I complete my project of designing a seven segment up counter using JK flip-flops in Proteus

#### joedone1

Joined Oct 1, 2017
16
How can I complete my project of designing a seven segment up counter using JK flip-flops in Proteus. I have completed analysis and designed the circuit but its not counting or working properly. I need help please, someone help

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#### dl324

Joined Mar 30, 2015
14,699
Welcome to AAC!

Is this homework?

Post your truth/excitation tables, Kmaps, and a schematic of the circuit. Also describe what kind of counter it is. Binary, BCD, gray, some odd sequence, ?? Lastly describe what it's doing wrong.

#### dl324

Joined Mar 30, 2015
14,699
Edited image for the convenience of others:

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#### joedone1

Joined Oct 1, 2017
16
Welcome to AAC!

Is this homework?

Post your truth/excitation tables, Kmaps, and a schematic of the circuit. Also describe what kind of counter it is. Binary, BCD, gray, some odd sequence, ?? Lastly describe what it's doing wrong.
Yes this is homework. However, I have not typed the analysis as per your request, however, I will scan the analysis and send later in the day.
Thanks very much Mr. Dennis, I am most appreciative

#### WBahn

Joined Mar 31, 2012
26,451
Make sure to indicate which signal is the lsb and msb of your logic and also which pin on the display is the lsb and msb.

#### joedone1

Joined Oct 1, 2017
16
Hello Denis,
Thank you

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#### JoeJester

Joined Apr 26, 2005
4,390
Can you post the question as your professor gave it to you?

#### dl324

Joined Mar 30, 2015
14,699
Why didn't you use don't cares in the kmap for JA?

Why didn't you include the don't cares for illegal counts in your truth table?

Counter is decimal up, A is MSB:

Kmaps for LSB:

EDIT: added Kmaps for D (LSB) and A (MSB).

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#### joedone1

Joined Oct 1, 2017
16
Can you post the question as your professor gave it to you?
Design a seven segment up counter (0-9) using JK Flip-Flops

#### joedone1

Joined Oct 1, 2017
16

#### dl324

Joined Mar 30, 2015
14,699
Thanks very much Sir, I am grateful. I will work on those areas spotted out and give you feedback
I think you'll find it helpful if you arranged the data in the kmaps so you can read the number from left to right.

This is my kmap for KD (D is the MSB in my design):

I use excel to enter my truth tables and the table above was set up for 5 variables. For the purposes of your problem, I just ignore the bottom half of the kmap.

To determine the count, you need to use the heading from the column, then row. If you put AB on the left and CD on the right, you can read the count more directly. You also wouldn't need to bother putting numbers in the cells because you'll be able to read them from the column/row headings.

If you order your truth table in gray code, it will be easier to transfer data from your truth table to the kmaps. Like this: (I only included the first 8 rows; which are the same as the data in your table)
EDIT: Actually you have 3 errors in those entries.

I use the convention that 'A' is always LSB. It's the way I was taught and reinforced by datasheets for counters from the likes of TI and National Semiconductor.

Apparently this is being taught differently in school now and now we need to ask which bit is LSB.

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#### joedone1

Joined Oct 1, 2017
16
I think you'll find it helpful if you arranged the data in the kmaps so you can read the number from left to right.

This is my kmap for KD (D is the MSB in my design):
View attachment 136347
I use excel to enter my truth tables and the table above was set up for 5 variables. For the purposes of your problem, I just ignore the bottom half of the kmap.

To determine the count, you need to use the heading from the column, then row. If you put AB on the left and CD on the right, you can read the count more directly. You also wouldn't need to bother putting numbers in the cells because you'll be able to read them from the column/row headings.

If you order your truth table in gray code, it will be easier to transfer data from your truth table to the kmaps. Like this: (I only included the first 8 rows; which are the same as the data in your table)
EDIT: Actually you have 3 errors in those entries.
View attachment 136344
I use the convention that 'A' is always LSB. It's the way I was taught and reinforced by datasheets for counters from the likes of TI and National Semiconductor.

Apparently this is being taught differently in school now and now we need to ask which bit is LSB.
Good Mr. Dennis,
I have done all what you asked me to do. However, after simulation using Proteus 8 Professional Schematic Capture, my circuit is reading some numbers (0, 8, 4, C, 2, A, 6, E, 1) leaving out numbers 3, 5, and 7. Please I need some help here with the solution. Again, these numbers are not counting sequentially, that is in order 0,1, 2, 3, 4, 5, 6, 7, 8 and 9. Please find attached the circuit diagram.
Thanks in anticipation.

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#### dl324

Joined Mar 30, 2015
14,699
Please I need some help here with the solution.
Your schematic is essentially unreadable; nothing is labeled, too many scenic routes, unnecessary wire bends, and too much whitespace.

Clearly the logic is wrong. Your initial table and Kmaps had errors. Post the data for your current design.

#### joedone1

Joined Oct 1, 2017
16
Your schematic is essentially unreadable; nothing is labeled, too many scenic routes, unnecessary wire bends, and too much whitespace.

Clearly the logic is wrong. Your initial table and Kmaps had errors. Post the data for your current design.
Good day JoeJester,
Please could you help me to finish the project.Actually the professor did not teach me anything about this.He only gave the question to research as assignment.i will be glad if you help me with the kmap diagram and the circuit diagram of this question of mine.
Question: Design a 7 segment up counter (0-9) using j-k flip flops
thank you

#### dl324

Joined Mar 30, 2015
14,699
Post your truth table and Kmaps.

#### joedone1

Joined Oct 1, 2017
16
Post your truth table and Kmaps.
Please find attached herewith the Kmaps and Truth table as per your request.

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#### dl324

Joined Mar 30, 2015
14,699
Please find attached herewith the Kmaps and Truth table as per your request.

You still have errors in your truth table and you don't have the don't care entries.

At count 5, you specify the next count as 12.

#### joedone1

Joined Oct 1, 2017
16
View attachment 136498
You still have errors in your truth table and you don't have the don't care entries.

At count 5, you specify the next count as 12.
Thanks very much Sir, for your prompt response. I have reworked on the Truth Table. Please find attached herewith. I have also crosschecked the Kmaps and they are in order, just in line with the New Truth Table

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#### dl324

Joined Mar 30, 2015
14,699
I have reworked on the Truth Table.
The current/next Q look okay; didn't check the other columns. Post your kmaps.

You still don't have the don't care lines in the table. Those lines will allow you to simplify the logic.

I think I mentioned this earlier. If you put your table in gray code order, it will be easier to transfer data to your kmaps.

#### joedone1

Joined Oct 1, 2017
16
The current/next Q look okay; didn't check the other columns. Post your kmaps.

You still don't have the don't care lines in the table. Those lines will allow you to simplify the logic.

I think I mentioned this earlier. If you put your table in gray code order, it will be easier to transfer data to your kmaps.