# Digital Works 95 - 7 Segment LED Help

#### Eddie McArdle

Joined Oct 20, 2016
4
So I've been given coursework to do on Digital Works 95 Software, and haven't actually used it at all before. I have been playing about with it, and can easily move around it and navigate through the different functions now, but I'm honestly clueless about how to do the following coursework.

I have to create a circuit with 3 sequences or bit generators as input, and a single 7 Segment LED output. The LED output should display the year (16) followed by my student number, and should go through the numbers automatically when I hit play. So the 7 Segment LED should consecutively show the numbers in a row 16XXXXXX (X being student number). Also I i have to build the circuit using only AND, OR, NOT, NAND and NOR logic gates to stimulate the counter.

Now I'm not straight up asking for an answer, as I obviously need to learn this stuff for later too, but the notes we have are very discrete and I've been trying to find a relevant TUT online with no luck, so if anyone could help at all and put me on the right path to getting this done, it'd be greatly appreciated. Cheers in advance!

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#### dl324

Joined Mar 30, 2015
12,931
Welcome to AAC!

In this forum, no one should just give you an answer. You won't learn that way.

Does the software you're using have flip flops? Or are you supposed to construct them using logic gates?

How are you supposed to handle duplicate digits in the student number?

#### Eddie McArdle

Joined Oct 20, 2016
4
Welcome to AAC!

In this forum, no one should just give you an answer. You won't learn that way.

Does the software you're using have flip flops? Or are you supposed to construct them using logic gates?

How are you supposed to handle duplicate digits in the student number?
Hi, thanks for the reply! The software does have flip flops, however we have to use logic gates for it, the following specifically: AND, OR, NOT, NAND and NOR

In terms of the duplicate digit, I've unfortunately got that problem, I might not be making sense saying this, but could I make an extra circuit for the duplicate number, but connect to the same 7 segment LED? (Again, I might be sounding foreign here as I've not a clue how to explain this stuff properly)

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#### dl324

Joined Mar 30, 2015
12,931
Students have asked similar questions and the solution is usually making a counter count in the sequence specified by the student ID. Doing that only with the gates you specified would be quite tedious.

If you post the exact wording of the problem, it might be clearer what you're expected to do.

#### dl324

Joined Mar 30, 2015
12,931
Someone else posted the same problem in the Digital Circuit Design forum. They posted a PDF describing the problem.

Based on that description, I see that all you need to do is design a 7 segment decoder to display numbers using 3 "bit generators".

I have never used the software in question, so I installed it. It's crude, but functional.

#### dl324

Joined Mar 30, 2015
12,931
This part of your assignment is 75% of your grade. Don't wait until the last minute to ask for help...

#### Eddie McArdle

Joined Oct 20, 2016
4
Sorry for this late reply, but managed to get it done! Circuit was actually easy to make once I created my truth table and equations, and I think I understand it now. But thanks for the help guys!

Quick question though... My circuit is rather big because I decided not to simplify my Boolean equations. It's not needed this time, but for future knowledge, does anyone know any good tutorials/sites that could help me simply my truth table equations? Would be nice to have my circuit look a little neater

#### dl324

Joined Mar 30, 2015
12,931
Post your equations and Kmaps.

A schematic might also be helpful because some of the min terms are common between segments.

#### Eddie McArdle

Joined Oct 20, 2016
4
Post your equations and Kmaps.

A schematic might also be helpful because some of the min terms are common between segments.
Sorry again for the long reply, but also managed to get the simplification done and the full circuit! (Just had to sit down for a while and concentrate on it). The last thing to do now is a bit of theory questions about circuits, but some of the questions don't really make sense to me so if you would know how to explain them a little better it'd be great;

How could the circuit be modified to display a binary number sequence? (The circuit I made)

4. Briefly describe what a decoder circuit is and give a practical example that uses a decoder circuit.
5. Briefly describe what an encoder circuit is and give a practical example that uses an encoder circuit.
(I've done research on question 4 and 5 and can kind of explain what they are, but don't know any practical examples)

#### dl324

Joined Mar 30, 2015
12,931
How could the circuit be modified to display a binary number sequence? (The circuit I made)
Since this is homework help, post your circuit and your ideas.
4. Briefly describe what a decoder circuit is and give a practical example that uses a decoder circuit.
5. Briefly describe what an encoder circuit is and give a practical example that uses an encoder circuit.
I think encode and decode can often be used interchangeably. Post your definitions and your ideas for applications of each.

Joined Nov 15, 2016
1
Sorry for this late reply, but managed to get it done! Circuit was actually easy to make once I created my truth table and equations, and I think I understand it now. But thanks for the help guys!

Quick question though... My circuit is rather big because I decided not to simplify my Boolean equations. It's not needed this time, but for future knowledge, does anyone know any good tutorials/sites that could help me simply my truth table equations? Would be nice to have my circuit look a little neater
can you please share your circuit I am also learning the same software so it will be much appreciated if you can share your circuit to my email please its sagradoamicus26 at gmail dot com

#### MrChips

Joined Oct 2, 2009
23,953
can you please share your circuit I am also learning the same software so it will be much appreciated if you can share your circuit to my email please its sagradoamicus26 at gmail dot com
Sorry, this is an educational site not a "do my work for me" site. If you wish to learn how to use the same software then ask a question related to something that is giving you difficulty.