Adding two numbers represented by two digital counters and two cascaded 4 bits adders (74hc283).

dl324

Joined Mar 30, 2015
12,819
May be some one here can point to one thats more affordable
My logic simulator of choice is Digital Works 3.0.5.0. It has a number of limitations, but it's free and you can make your own components fairly easily. The commercial parts aren't usable because they use IC package symbols that don't do anything to help convey circuit intent. It doesn't assign component designators, but you can add pin numbers to symbols you create (this deficiency occurred to me much too late).

Schools seem to like Logisim because there's some automated test capability.
 

andrewmm

Joined Feb 25, 2011
1,268
My logic simulator of choice is Digital Works 3.0.5.0. It has a number of limitations, but it's free and you can make your own components fairly easily. The commercial parts aren't usable because they use IC package symbols that don't do anything to help convey circuit intent. It doesn't assign component designators, but you can add pin numbers to symbols you create (this deficiency occurred to me much too late).

Schools seem to like Logisim because there's some automated test capability.
Thank you

so back to the IOP,
I suggest you simulate using Digital works,
 

Thread Starter

Eshawn

Joined Oct 5, 2019
31
Thank you. Very nice schematic. Is it just a schematic or you also simulated the addition with the clock inputs?
 

dl324

Joined Mar 30, 2015
12,819
Is it just a schematic or you also simulated the addition with the clock inputs?
I simulated with Digital Works. If I knew what you were trying to accomplish and the order of the bits in the adders, I'd try the different clocks.

The CD4040 is a generic 4 bit binary ripple counter I designed and cascaded to 12 bits. I removed the set and carry out functionality my counters had. The 4 bit full adder is my own design, but is functionally equivalent to HC283. The hexadecimal decoder is an implementation of the MC14493 ROM based decoder that will be hard to find. My original design was implemented with a couple dozen gates. The ROM based decoder should simulate more efficiently.

EDIT: the 4 bit adder is actually the 1 bit full adder that's included with the simulator.

The only components that exist in Digital Works as distributed are the 7 segment display, clock, and switch.
 
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Thread Starter

Eshawn

Joined Oct 5, 2019
31
I simulated with Digital Works. If I knew what you were trying to accomplish and the order of the bits in the adders, I'd try the different clocks.

The CD4040 is a generic 4 bit binary ripple counter I designed and cascaded to 12 bits. I removed the set and carry out functionality my counters had. The 4 bit full adder is my own design, but is functionally equivalent to HC283. The hexadecimal decoder is an implementation of the MC14493 ROM based decoder that will be hard to find. My original design was implemented with a couple dozen gates. The ROM based decoder simulate more efficiently.

The only components that exist in Digital Works as distributed are the 7 segment display, clock, and switch.
Thanks a lot for trying to do the software simulations.
Could you tell me if you used the clock inputs of 1 khz and 512 hz for the two counters and did you set a time base of 16 hz? Also the counters should be reset in the last quarter of the time base cycle or in other words, in the second half of the logic low of the time base as I tried to show the signals in my schematics.
Considering that the adder configuration is totally equivalent to the 74hc283, I will greatly appreciate it if you simulate the circuit with the parameters I specified.
 

dl324

Joined Mar 30, 2015
12,819
I will greatly appreciate it if you simulate the circuit with the parameters I specified.
Might if you explained what you you're trying to accomplish, clarify the order of the bits in the bussed signals, and show the phase relationship of the 4 clocks.

EDIT: removed extraneous word.
 
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Thread Starter

Eshawn

Joined Oct 5, 2019
31
Now I am going to replace the schematics to include the signals I have in mind while the order of the bits in the bussed signals. Also, there are 2 clocks not 4 and as a note, the cd4040 or 74hc4040 are 12 stage ripple-carry binary counters not 4. I hope the information is enough for you to perform the software simulation.
 

andrewmm

Joined Feb 25, 2011
1,268
Now I am going to replace the schematics to include the signals I have in mind while the order of the bits in the bussed signals. Also, there are 2 clocks not 4 and as a note, the cd4040 or 74hc4040 are 12 stage ripple-carry binary counters not 4. I hope the information is enough for you to perform the software simulation.
Can I suggest @Eshawn, that were here to help you, and learn new techniques, info ,
not do the work for you ..
 

Thread Starter

Eshawn

Joined Oct 5, 2019
31
Do the work for me?

1- dl324 started her response by complaining about my schematic and I responded to her.

2- Because she did not like my schematic, I did her a favour to use hers although I was very happy with mine as it clearly showed what I was talking about.

3- None of you have been of any real help for me but I folded you with my appreciations to be nice. Obviously you never dealt with a circuit which I showed here.

4- If you answer a thread, make sure you have the adequate technical knowledge to provide some real solution. All your guesses and complaints made my post so crowded that no one got a chance to offer me areal solution.

5- At this point, I have a far better understanding than you have about what is going on in that circuit.

6- I lost a whole day dealing with you people for this post. I set my account to hide the conversation as I felt disgusted by last writings to me and instead someone that could not be anyone other than your websites’s admin reversed the hiding as if I wanted to see the conversation.
7- delete this ridiculous conversation and do not send your time consuming and not helpful comments to me anymore.
 

MrChips

Joined Oct 2, 2009
23,286
That is very unfortunate that your short visit here on AAC did not meet your expectations. I can assure you that there are many members here that collectively have hundreds of years of experience in this field and who would be more than happy to assist you with your project.

In defense of AAC and its esteemed members I would suggest that you consider the following points.

1. Assisting someone online is not always the most ideal situation. We are not able to see your test setup. We are not able to inquire immediately your level of expertise, your objectives, and the big picture that you have in your mind. Too often it takes many questions and answers back and forth in order to extract the correct information.

2. Most often when someone requests more information it is for clarification and is never intended to test your knowledge or ability.

3. Most often a circuit schematic is our only and primary means of communication when it comes to electronic circuits. Professionals properly trained in this field have become accustomed to communicating in this manner using well established guidelines. When someone suggests that a circuit schematic should be documented in a particular manner it is a recommendation to become familiar with the accepted practices.

4. ACC forum is a community of members. Never berate or scold a member when their responses do not fulfill your requirements. Be humble and grateful for the service being provided.

5. Watch your words. Be patient. Learn to accept guidance. Provide information when asked. No member here on AAC is here intentionally to give another member a hard time.

You never responded to my question as to why you are doing this.
You are fixated on your specific problem and have shown no desire to provide us with the big picture. Very often when we find out the real objectives a better solution can be provided and the specific problem disappears.

On your specific problem you are attempting to add two 16-bit values. Have you isolated and tested what happens when you add two 4-bit values?
15 + 15 = 30
You can never get a result of 31 by adding 15 + 15...
unless... here it comes...
Carry-in is 1.
 

Thread Starter

Eshawn

Joined Oct 5, 2019
31
That is very unfortunate that your short visit here on AAC did not meet your expectations. I can assure you that there are many members here that collectively have hundreds of years of experience in this field and who would be more than happy to assist you with your project.

In defense of AAC and its esteemed members I would suggest that you consider the following points.

1. Assisting someone online is not always the most ideal situation. We are not able to see your test setup. We are not able to inquire immediately your level of expertise, your objectives, and the big picture that you have in your mind. Too often it takes many questions and answers back and forth in order to extract the correct information.

2. Most often when someone requests more information it is for clarification and is never intended to test your knowledge or ability.

3. Most often a circuit schematic is our only and primary means of communication when it comes to electronic circuits. Professionals properly trained in this field have become accustomed to communicating in this manner using well established guidelines. When someone suggests that a circuit schematic should be documented in a particular manner it is a recommendation to become familiar with the accepted practices.

4. ACC forum is a community of members. Never berate or scold a member when their responses do not fulfill your requirements. Be humble and grateful for the service being provided.

5. Watch your words. Be patient. Learn to accept guidance. Provide information when asked. No member here on AAC is here intentionally to give another member a hard time.

You never responded to my question as to why you are doing this.
You are fixated on your specific problem and have shown no desire to provide us with the big picture. Very often when we find out the real objectives a better solution can be provided and the specific problem disappears.

On your specific problem you are attempting to add two 16-bit values. Have you isolated and tested what happens when you add two 4-bit values?
15 + 15 = 30
You can never get a result of 31 by adding 15 + 15...
unless... here it comes...
Carry-in is 1.
Never reproduce other people‘s schematics without their permission. That is unlawful.
Always be respectful to people who have reasons to ask you to delete their account..
 
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