Discussion in 'Homework Help' started by christophee, Sep 21, 2012.

1. ### christophee Thread Starter New Member

Jan 15, 2012
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0
We are tasked to create a digital circuit of a password game where there are supposed to be four buttons. The user must know the proper sequence in which the four buttons are pushed. We can either input a password internally or the user can change the password by themselves (bonus). Please help me with the circuitry. I am really lost to where and how to start.

Here's the game:
There are four buttons, A B C D
There is an inner password let's say C-A-D-B.
The user must push buttons in order to get the right password code.
If the first button is wrong, it will display red LED and alarm/sound then a reset button must be pushed to start again.
If the user then guessed the correct code of C-A-D-B, a green LED will light in every right guess of the sequence and a Congratulations-you-are-right LED will light up.

Last edited: Sep 21, 2012
2. ### t06afre AAC Fanatic!

May 11, 2009
5,939
1,222
Schoolwork I presume Well the meaning is that you shall use what you have learned in previous courses. To solve this task. Like do you have any micro-controller or digital logic courses.
We do not mind helping out students here but do not expect that we will serve you a solution on a silver plate.

3. ### Wendy Moderator

Mar 24, 2008
20,772
2,540
Think serial shift register.

There is more than one way to do this.

4. ### christophee Thread Starter New Member

Jan 15, 2012
9
0
hello there! We do have digital logic courses, but this project is new to us. I have an idea on how to do it but some things are just not right.

5. ### absf Senior Member

Dec 29, 2010
1,493
374
What logic chips did you use?

I'd start with 4 flip flops like 4013 or 7474 and 4 push button switches.

Allen

6. ### WBahn Moderator

Mar 31, 2012
18,087
4,917
Come on, we are not mind readers. Throw us a bone!

What type and level of course is this? This will give us a hint on the kinds of techniques that are reasonable to discuss.

What 'things' are just not right? How can we possibly help get them right unless you tell us what they are?

What are your thoughts about how to approach the problem? What have you tried thus far?

Have you developed a state diagram?

Jun 22, 2012
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8. ### christophee Thread Starter New Member

Jan 15, 2012
9
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We managed to make the design. We have series of D flip flops both for the password itself and the guess of the user. Then a comparator to compare the password and the guess. Our problem now is we do not know which values of resistors and capacitors to use in series or parallel in the circuit. Please help?

9. ### WBahn Moderator

Mar 31, 2012
18,087
4,917
To even have a shot at providing an answer to that, we need to see the circuit and where you are planning to use resistors and capacitors and why you are wanting to use them (what purpose they are intended to serve). We can also then point out other places where you might need them.

10. ### christophee Thread Starter New Member

Jan 15, 2012
9
0

so here's our circuit. Hmmm, There are about 34 IC's here and we are having a hard time hardwiring/etching PCB. please help? I'll post the schematic later. It's too big to attach.

This is composed of D flipflops, parallel registers, multiplexer, and magnitude comparator. Will there be easier design for this? any suggestions? thanks!

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Jan 15, 2012
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