# next step after create Truth Table to make 7 segment LED counter by using Digital Works 95

Thread Starter

#### Shen Joo

Joined May 23, 2018
12
It's a poor choice of words to use "counter" in this sentence; the display doesn't count anything. It would have been more appropriate just say 7 segment display instead and get rid of the parenthetical.
The fact that the question says to take "binary input" using only 3 sequencers is in conflict because it takes 4 bits to represent 8 as a binary number.
How do you plan to handle the instances of "77"? Why did you change the year to 17?

When is this assignment due? You've been working on it for several days.
1. The assignment due date is before August 2018

2. The question paper shown likes below picture:

#### dl324

Joined Mar 30, 2015
13,841
2. The question paper shown likes below picture:
The question is poorly worded. There's no counter in the circuit you're being asked to design. A 7 segment display is a display, not a counter.

The problem said the number generated should start with the last two digits of the year. Why are you using 17? This is 2018.

Other than trying to interpret what the poorly worded problem wants, this problem isn't difficult. I assumed you were supposed to generate binary numbers representing the year and your student ID with the sequencers, i.e. sequencer output is 0001 when you want 1, 1000 when you want 8.

Another interpretation could be that you can decode any arbitrary sequence of numbers using 3 sequencers as long as you don't have more than 8 unique numbers. So you could make the 8 possible combinations from three sequencers decode to any numbers you wanted.

You've probably done similar problems in your classes, so you have some context that can be used to interpret what your teacher wants.

Thread Starter

#### Shen Joo

Joined May 23, 2018
12
Latest news:

I already done the circuit in Digital works 95 but it only show "1" only and it not automatic run himself next digit likes 1 8 7 8 7 7 2 5

#### absf

Joined Dec 29, 2010
1,968
The sequencer is actually programmable. Right-click on the circle next to "sequence" and using sequence editor to enter up to up to 64 bit states. This would control the bit inputs of the 3 sequencer.

Also use the Circuit/Clock speed to control the speed of the clock to slow down the display..

Just for fun, this is how I did it.

Last edited:
Thread Starter

#### Shen Joo

Joined May 23, 2018
12
The sequencer is actually programmable. Right-click on the circle next to "sequence" and using sequence editor to enter up to up to 64 bit states. This would control the bit inputs of the 3 sequencer.

Also use the Circuit/Clock speed to control the speed of the clock to slow down the display..

View attachment 153844

Just for fun, this is how I did it.

View attachment 153846
So next how to let the circuit diagram automatically run the number (without adding any other devices)

For example, how should the "Sequence" part be adjusted?

Because I got stuck in here.

#### absf

Joined Dec 29, 2010
1,968

There are 8 states from the 3-bit-sequencer. From the "Logic History" chart, the states starts with 000 to 111.

Naming the 3 sequencers as sequencer_0 to sequencer_2, edit sequencer_0 as '01010101', sequencer_1 as '00110011' and sequencer_2 as '00001111', then on the first clock, the 3 squencer would output '000' and the final state would be '111' on the 8th clock ....

Code:
See:         01010101         seq_0
00110011         seq_1
00001111         seq_2
^
|------ clock #1

Allen

#### dl324

Joined Mar 30, 2015
13,841
So next how to let the circuit diagram automatically run the number (without adding any other devices)
You use the "Run" button to have the sequencers cycle automatically. This screen capture is from a newer version, but it's the same in your version as I recall.

In the bottom row, the first button is run; followed by stop, pause, and single step. Single step has a half and full clock option.

For example, how should the "Sequence" part be adjusted?
You should set them to count the numeric sequence you want to display using the steps @absf outlined. Since you're using 3 sequencers, to display 8, you need to enter the appropriate number.

#### absf

Joined Dec 29, 2010
1,968
There are some mistakes in your logic.

I single stepped the simulation and got the pattern "1775858E" instead of "18787725"

All the digits 1 7 8 2 are there. The last "5" was decoded as "E"

Thread Starter

#### Shen Joo

Joined May 23, 2018
12
There are some mistakes in your logic.

I single stepped the simulation and got the pattern "1775858E" instead of "18787725"

All the digits 1 7 8 2 are there. The last "5" was decoded as "E"

View attachment 153910
I already create a new circuit again but this now show "17728785"
I not sure what is wrong in this circuit...

#### dl324

Joined Mar 30, 2015
13,841
I already create a new circuit again but this now show "17728785"
I not sure what is wrong in this circuit...
Post your truth table.

#### WBahn

Joined Mar 31, 2012
26,398
What have you done to troubleshoot the circuit?

Which segments are working correct and which segments are not?

#### dl324

Joined Mar 30, 2015
13,841
I already create a new circuit again but this now show "17728785"
I not sure what is wrong in this circuit...
I simulated the circuit. It works, but the logic is unnecessarily complex because you don't understand what the problem wants.