So ain't there a binary to BCD working IC out there?

They're no longer manufactured.

If you needed to breadboard a circuit, you can make them from 8x32 bit PROMs. In response to a problem, a member designed one using a 32Kb EPROM. I extended on his work and designed one using a 256Kb X 16 EPROM.

EDIT: You can probably find some parts that ship from China. If you're lucky, you might actually get an authentic, functioning chip. But, if you're not paying a lot, it's probably fake. Parts that are no longer being manufactured command a premium.

 

They're no longer manufactured.

If you needed to breadboard a circuit, you can make them from 8x32 bit PROMs. In response to a problem, a member designed one using a 32Kb EPROM. I extended on his work and designed one using a 256Kb X 16 EPROM.

EDIT: You can probably find some parts that ship from China. If you're lucky, you might actually get an authentic, functioning chip. But, if you're not paying a lot, it's probably fake. Parts that are no longer being manufactured command a premium.

Speaking of, i found one, and it's highly expensive, I'm gonna give it a shot tommorow if the IC arrives in time.

And here's a thing I just saw on YouTube, about an algorithm called "shift, if greater than 5 then add 3"
You think it's useful in my case?
Here's the link:

 

I'm done learning btw, it's just a final project to make sure I'm ready to pass the course

So the course is over. What makes you think that you should pass?

 

So the course is over. What makes you think that you should pass?

The fact that it's not an essential course for my BC, and one way or another, they force me to pass it and i don't have time and money to waste.
I'm suppose to learn biomedical engineering stuff in there, not logic circuits!
Also i already know how to work with arduino and Raspberry Pi and some other microcontrollers and thinker boards.
With all due respect sir, these type of projects and courses, are completely useless for me i think...

 

The fact that it's not an essential course for my BC, and one way or another, they force me to pass it and i don't have time and money to waste.
I'm suppose to learn biomedical engineering stuff in there, not logic circuits!
Also i already know how to work with arduino and Raspberry Pi and some other microcontrollers and thinker boards.
With all due respect sir, these type of projects and courses, are completely useless for me i think...

That is your opinion. I am a teacher in biomedical engineering and you'd think that I ought to know what is important for you to learn.

 

That is your opinion. I am a teacher in biomedical engineering and you'd think that I ought to know what is important for you to learn.

Every teacher is my teacher too.
Hope you do fine through this corona virus pandemic.
At this point, only passing this course helps me, so if you don't wanna help, I'm done talking.
Thanks for your wise words btw.
Peace

 

And here's a thing I just saw on YouTube, about an algorithm called "shift, if greater than 5 then add 3"
You think it's useful in my case?

No. They didn't get the algorithm, called double dabble, correct. The 5 should be 4:


Beware of giving too much credence to things you find on the internet. YouTube is particularly bad. There are a lot of so called experts who are actually idiots.

Speaking of, i found one, and it's highly expensive, I'm gonna give it a shot tommorow if the IC arrives in time.

You'd likely be better off if you bought a 32x8 PROM and burned your own. But let us know how it goes. I'm always interested in learning about sources of hard to find IC's that need to be avoided.

In Proteus, you could make a macro or block (or whatever they call custom devices), that does the conversion. Here's the truth table:


I built one for the logic simulator I use...

 

No. They didn't get the algorithm, called double dabble, correct. The 5 should be 4:
View attachment 212257

Beware of giving too much credence to things you find on the internet. YouTube is particularly bad. There are a lot of so called experts who are actually idiots.

You'd likely be better off if you bought a 32x8 PROM and burned your own. But let us know how it goes. I'm always interested in learning about sources of hard to find IC's that need to be avoided.

In Proteus, you could make a macro or block (or whatever they call custom devices), that does the conversion. Here's the truth table:
View attachment 212258

I built one for the logic simulator I use...

Thanks again, I'm waiting for the delivery to see if it works.
Also i asked my professor for 32x8 PROM, and she said I'm not allowed to use one, neither in simulation, nor in real circuit.

 

Why did you design asynchronous counters?

Design the counters and post your work if you're still having problems. It shouldn't take long to do it.

Seems like a pretty low bar to pass a class. What is the name of the class, what level is it, and which school?

Do you mind to have a look at this synchronous circuit?
First JKFF's output is always 0.

 

Do you mind to have a look at this synchronous circuit?
First JKFF's output is always 0.

I am not familiar with Proteus nor am I anything of an expert in sequential logic, but I've been working with it recently. Perhaps I can offer a little insight. If I understand the notation of Proteus, Pink (red?) indicates a HIGH signal, Blue indicates a LOW signal, and Grey indicates a disabled or unconnected pin. Your first FF (U1) has the J & K inputs tied together creating a toggle circuit which flips the output (Q) every clock cycle.

https://www.allaboutcircuits.com/textbook/digital/chpt-10/j-k-flip-flop/

The part that caught my eye is that your asynchronous RESET line is held HIGH. If this is not an inverted input, then you are holding the output (Q) of U1 LOW.

https://www.allaboutcircuits.com/textbook/digital/chpt-10/asynchronous-flip-flop-inputs/

You may wish to read the "Education - Textbooks - Vol IV: Digital" section of this site. There are many useful articles including this one which may be related to what you are trying to do.

https://www.allaboutcircuits.com/textbook/digital/chpt-11/binary-count-sequence/

 

I am not familiar with Proteus nor am I anything of an expert in sequential logic, but I've been working with it recently. Perhaps I can offer a little insight. If I understand the notation of Proteus, Pink (red?) indicates a HIGH signal, Blue indicates a LOW signal, and Grey indicates a disabled or unconnected pin. Your first FF (U1) has the J & K inputs tied together creating a toggle circuit which flips the output (Q) every clock cycle.

https://www.allaboutcircuits.com/textbook/digital/chpt-10/j-k-flip-flop/

The part that caught my eye is that your asynchronous RESET line is held HIGH. If this is not an inverted input, then you are holding the output (Q) of U1 LOW.

https://www.allaboutcircuits.com/textbook/digital/chpt-10/asynchronous-flip-flop-inputs/

Thanks for your humble answer
I double checked and your dang right.
I forget to check JKFF's reset pin state before i make 'em, and by default i set 'em to HIGH.

 

They're no longer manufactured.

If you needed to breadboard a circuit, you can make them from 8x32 bit PROMs. In response to a problem, a member designed one using a 32Kb EPROM. I extended on his work and designed one using a 256Kb X 16 EPROM.

EDIT: You can probably find some parts that ship from China. If you're lucky, you might actually get an authentic, functioning chip. But, if you're not paying a lot, it's probably fake. Parts that are no longer being manufactured command a premium.

The IC arrived about an hour ago, so i made the circuit on a bread board and guess what?! It kinda not working and i think it's dead because of the output which is not stable at all...
So that was a total waste of money unfortunately

Speaking of, i think i found a way to make a double dabble circuit.
I mean i think it should be a mixture of a comparator, an adder, a multiplexer and a shift register, but i still don't know if there is such a circuit for real.

 

The IC arrived about an hour ago,

That was fast. Who did you buy it from and how far did they have to ship?

kinda not working and i think it's dead because of the output which is not stable at all...

How do you have it connected? Do you have decoupling caps?

EDIT: One IC doesn't do you much good anyway. You need 3 to convert 8 binary bits.

i think i found a way to make a double dabble circuit.
I mean i think it should be a mixture of a comparator, an adder, a multiplexer and a shift register, but i still don't know if there is such a circuit for real.

My implementation took 18 gates.

If anyone actually needed to implement this conversion, they'd likely use a look up table like National and TI did. I actually burned a 16bit EPROM. I only checked a few locations because my only concern was byte order. My programmer reads 2 bytes from the data file for each address and I wasn't absolutely certain of the order.

 

That was fast. Who did you buy it from and how far did they have to ship?
How do you have it connected? Do you have decoupling caps?

EDIT: One IC doesn't do you much good anyway. You need 3 to convert 8 binary bits.
My implementation took 18 gates.

If anyone actually needed to implement this conversion, they'd likely use a look up table like National and TI did. I actually burned a 16bit EPROM. I only checked a few locations because my only concern was byte order. My programmer reads 2 bytes from the data file for each address and I wasn't absolutely certain of the order.

I bought them from a friend of my father, selling and fixing old TV's and radios etc.

I asked the seller about using it, and he referred me to the datasheet, so i read and connect them properly.
But no, i used two of them, and when i connected the VCC and GND of them to power source to test if they are working, the outputs were continuesly changing from 1 to 0 and back so i asked the seller and he said they are probably dead, but thankfully he paid me back

So now that i have no choice left, i emailed the details to the professor and I'm waiting for her to answer.
I offered three methods instead of using 74185:
First, using double dabble circuit, which will take me so long to design i guess.
Second, making the counter without flip flops and based on BCD and binary adders.
Third, to program a microcontroller to do the conversation part.

Is there any other option you think?!

EDIT: i totally forgot about the first project, I'll post it now.

 

So here is the schematic of the first project and it should get A and B (both 4 bit binary numbers from 0000 to 1001) and do A+B and A-B and if the result magnitude is negative, show (-) sign before the number.

selected parts (red ones) are to produce (-) sign for subtracting exceptions like 0-9 or 0-0
But some of them still exist, like 8-0 or 9-0 produce the negative sign too.

I also wanted to use a comparator IC, but again my professor told me not to do...

 

Your professor is a tough cookie. Good for her!

 

Is there any other option you think?!

How can we say? I asked you to post the complete text of the problem so we can read for ourselves what you're supposed to do. You still haven't done that.

If you're designing a counter that counts from 00-99, why do you think you need a binary to BCD converter? Two BCD counters and the BCD to seven segment decoders are all you need.

 

Your professor is a tough cookie. Good for her!

I can't believe your still following this topic sir
Yes, good for her and bad for me

 

How can we say? I asked you to post the complete text of the problem so we can read for ourselves what you're supposed to do. You still haven't done that.

If you're designing a counter that counts from 00-99, why do you think you need a binary to BCD converter? Two BCD counters and the BCD to seven segment decoders are all you need.

Because it's not written anywhere, she just told me what she wants with some explanation and i told you all i knew.

The problem is, she insists to use flip flops to make that synchronous counter.

 

The problem is, she insists to use flip flops to make that synchronous counter.

Post your work for the counter design. If you're not sure where to start or what to do, you can bounce ideas off us.

When is this assignment due?