# Designing a circuit for a 7 Segment LED counter to display 17 followed by your student number.

#### HellasArmy

Joined Oct 20, 2017
4
Hello. I just want some feedback if is possible for my coursework so far. Also, i just want to know if the equations are correct to design the circuit in Digital Works 95.

The Problem:

Design a circuit to take binary inputs and display a number on the counter. The counter needs to display the number 1 followed by 7 to indicate the current year the coursework was done (i.e. 2017). Then this will be followed by your unique student ID number (person number). This will mean that everybody will have a unique problem to solve as no two students have the same student number. So if your student number was 123456 then your counter would need to display 17123456. Build a circuit using only AND, OR, NOT, NAND and NOR logic gates to simulate the counter. You should use 3 sequencers (I used 4 sequencers because i have 8 in my student ID) or bit generators in your circuit as input. Draw your circuit using Digital Works 95. The numbers should change automatically without any user input.

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#### dl324

Joined Mar 30, 2015
16,665
Welcome to AAC!

Not sure what your intent is with the inputs. I think you're confusing the BCD input to your decoder with the data that you need to code in the sequence generators.

You have done a specialized BCD to seven segment decoder in that you've omitted the digits that aren't used. Without Kmaps, someone would have to do the design to check your work.

#### HellasArmy

Joined Oct 20, 2017
4
Hello Mr Dennis,

I will try today to design my circuit in Digital Works 95 and i will see if is working or not.

#### RBR1317

Joined Nov 13, 2010
712
(I used 4 sequencers because i have 8 in my student ID)
But notice that the input from the 'A' sequencer never changes, so what actual information is added by having the fourth sequencer?

#### HellasArmy

Joined Oct 20, 2017
4
Aaaahh never mind . I have done it successfully with 3 sequencers. You do not need 4 sequencers to represent numbers 8 and 9 with Digital Works 95. Here is my circuit with the correct numbers of my student ID.

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#### dl324

Joined Mar 30, 2015
16,665
Here is my circuit with the correct numbers of my student ID.
1. Keep all wires multiples of 90 degrees.
2. Don't use colors.
3. Print to pdf so you don't have that annoying grid.
If I was your instructor, I'd give reduced credit for sloppy work.

Part of a hex to 7 segment decoder I did:

The labeling is helpful if I make mistakes in the kmaps or wiring. For that reason, I don't attempt to simplify the logic until I verify that it works.