4000 and 7400 Series Integrated Logic Circuit IC's - Page 3 — Parallax Forums

4000 and 7400 Series Integrated Logic Circuit IC's

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• Posts: 22,978
You really need only one gate to construct any combinatorial logic circuit you want. It's the NAND (not-and) gate:

https://en.wikipedia.org/wiki/NAND_logic

-Phil
• Posts: 14,662
You really need only one gate to construct any combinatorial logic circuit you want. It's the NAND (not-and) gate:

https://en.wikipedia.org/wiki/NAND_logic

-Phil

Yup, or you can use it's close sibling the NOR gate... https://en.wikipedia.org/wiki/NOR_logic

There are even Tiny Logic gates that let you select what gate you have, from a single part code, called Configurable Logic - see 1G57 1G58 1G97 1G98 etc
• Posts: 1,194
edited 2018-06-04 00:43
Thanks Mike

Maybe you will understand it better if you see the NOT or NO gate.

It is on the next page.Page 19

A YES gate passes through a 1 as a 1.A 0 as a 0.

It's a foundation for all logic gates.

Not that hard to comprehend.

• Posts: 1,194

Mike

Here's the NOT gate diagram.This time it has the two 4.5 volt labels on it.

• Posts: 1,194

Here's a fun fact.

That transistor replaced vacuum tubes that were called Triodes.

That's where Diodes comes from.

Forging ahead.Have to connect up 4001 logic gate IC.
• Posts: 1,515
microcontrolleruser,

Compare your "Yes" gate to a basic transistor "switch" circuit, and what do you notice?

Tri- means three and Di- means two.
A Triangle has 3 angles and Carbon Dioxide (CO2) has 2 Oxygen atoms.

Audio purists swear that tube amplifiers are superior and some musicians still use tube equipment so tubes (valves for the rest of the English speaking world) are not dead.
• Posts: 1,194
edited 2018-06-04 02:59

You're just saying that to irk me.

Got rid of a Peavey Stereo Chorus 400 head when I lost interest in music.

You don't EVEN want to hear about the rest of the stuff that went bye bye.

VERY painful to even think about it!
• Posts: 1,194

Back on track.

Have to put 4001 IC on Learning Lab.
• Posts: 8,690
Thanks Cluso

First experiment on page 24.

Shows why our R/C circuits would not run by themselves.

Experiment runs R/C circuit through two 4001's.

Truly amazing!

The magic of electronics!
• Posts: 1,194

Thanks Kwinn

'The magic of electronics!'

Yes.And we are little magician's apprentices I suppose.

Oh! One of the basic gates is how they make Register and Shift Register's.Counters too I think.

The pieces are starting to fall together.At least a little.
• Posts: 17,703
Never heard of a "YES" gate. Some concocted explanation, but never heard of in my 50 year electronics and computer career.
• Posts: 22,978
Cluso99 wrote:
Never heard of a "YES" gate. Some concocted explanation, but never heard of in my 50 year electronics and computer career.
It's also called a "wire."

-Phil
• Posts: 10,193
Cluso99 wrote: »
Never heard of a "YES" gate. Some concocted explanation, but never heard of in my 50 year electronics and computer career.

YES ..... I know what you mean

I cut my teeth on discrete transistor NOR gates as these were very easy to construct with 2 or 3 resistors and a transistor. The most basic building block of logic gates NEEDS to invert and therefore NOT, therefore NOR or NAND. Absolutely no such thing as a "yes" gate as it is an improper made-up term for a buffer.

The NAND gate became popular with 7400 series gates and the most ubiquitous of these is of course the 7400 quad 2-input NAND gate. I designed my very first video terminal computer from this family and its 74LS cousins with about 6 relatively large pcbs that plugged into repurposed S-100 card edge connectors. There were boards that handle the character ROM and programmable character RAM, address buffers and X and Y scaling (since I didn't know what character size to use), etc. Then there was my prized 2650 PC1001 board with a whole whopping 1k of RAM and 1K of ROM, but I had an 8k memory board board, so I had "plenty" of memory.

So yes, like many people on this forum we are very familiar with logic gate chips of all types, 7400 and 4000 series included although we rarely design with them these days, only perhaps the odd gate or buffer required. I would have thought this type of thread more appropriate for a basic digital electronics forum though as designing with microprocessors require a good knowledge of digital electronics because even at the assembly level we deal with AND/OR/NOT/XOR etc.
• Posts: 21,233
Have we decided yet if "YES" is some kind of logical operator, like AND, OR or NOT?

If so it must be equivalent to two NOTs in series. Which we can optimize down to a piece of wire.

Or is it just some kind of logical operator that always produces a "YES" output no matter what the input is.

If so it's just a signal connected to 5v permanently (In a TTL implementation)

If you measure the characteristics you will find that a vacuum tube triode or like has the most linear transfer characteristics of any amplifying device ever invented.

Transistors are so terrible and crude by comparison they are best used only for digital circuits

I recall having a book on digital electronics when I was about 13 years old. When the 7400 series was still a thing and the CMOS 4000 series was new). Took me a long while to wrap my head around how the Master-Slave JK Flip Flop worked. When the penny dropped, wow, what magic! Still one of my favorite circuits ever.

Years later we built a 3 bit binary counter, 3 flops in series, out of 1 meter long pneumatic actuators and spool valves. It was the most impressive counter I have ever seen running!
• Posts: 1,194

'Never heard of a "YES" gate'

Well.You can learn something new every day.Technically.Probably Forrest Mims in his book is the only person that uses it.True.

Here's the explanation for a NOT gate or an inverter.

https://en.wikipedia.org/wiki/Inverter_(logic_gate)

YES gate is a teaching aid.Just to balance it in the lesson.

There is YES gate and a NO or NOT gate.Makes sense to me.

• Posts: 1,194

Thanks Heater

Great story!

Will figure out what to build on it.
• Posts: 10,193
'Never heard of a "YES" gate'

Well.You can learn something new every day.Technically.Probably Forrest Mims in his book is the only person that uses it.True.

Here's the explanation for a NOT gate or an inverter.

https://en.wikipedia.org/wiki/Inverter_(logic_gate)

YES gate is a teaching aid.Just to balance it in the lesson.

There is YES gate and a NO or NOT gate.Makes sense to me.

Perhaps the term might be used by some teachers but while you can search Digikey/Mouser or any logic gate manufactuers website for NOR/NAND/AND/OR/XOR there are no YES gates. NOT is a term that applies to inversion of a logic level so therefore you have NOR = NOT OR etc but a single input NOT gate is normally called an inverter and a single-input non-inverter is simply a buffer. There are no terms for YES gates ever that you can design with.

I'm not sure who you are trying to teach but you don't seem to accept what we as teachers are trying to tell you either.
• Posts: 17,703
edited 2018-06-04 07:40
Peter, was that 8K RAM memory board made of 64 x 2102's by chance?

Multivibrators followed the miniature and maxi crystal sets in my youth. Then Ham radios.

Of course, the transistors came from DTL and TTL ex IBM computer circuit boards.
• Posts: 1,194

Here's the page from the book.

A YES gate is a buffer.

• Posts: 1,194

' a single-input non-inverter is simply a buffer.'

A teacher calls it a YES gate and you are making a big deal about it.

Sounds kind of inflexible to me.
• Posts: 17,703
Well, do you want to learn the right terms, or do you want to learn something that is incorrectly named? You choice. If it's the latter, you are not likely to get much more help though.
• Posts: 10,193
' a single-input non-inverter is simply a buffer.'

A teacher calls it a YES gate and you are making a big deal about it.

Sounds kind of inflexible to me.

YES, you do sound very inflexible to me by your making a big deal out of it. Now please try to order a "YES" gate from any supplier at all.

Perhaps institutions of higher learning should follow the "Radio Shack" tutorial to suit you? But you are missing the point, in that you don't know these things but you nonetheless are trying to teach those who do know these things. As a Parallax forum we are happy to help all but can only help those you are genuine and accept the help. I have noticed that you have been very rude to some respected members of this forum because they were trying to help you. There is a point, if not already at which this thread will attract the attention of the moderators.

• Posts: 1,194

'do you want to learn the right terms'

Yes.I do.

• Posts: 10,193
edited 2018-06-04 08:35
You can find support for almost anything
It doesn't make you right though.
• Posts: 17,703
I thinks it's time for the thread to be sunk.
The information here is likely to misinform those who genuinely want to learn the correct way.
• Posts: 2,013
I would tend to agree. We've bashed the discussion over the head with all sorts of widgets that it's becoming bruised. So let's move onto something else.
• Posts: 21,233
I have come to a conclusion....

The whole idea of a YES gate is fundamentally wrong.

"YES" or "NO" are answers to questions. They are values. As there is only two possibilities we can map them onto more typical logic notions, such as "HIGH" and "LOW", "TRUE" or "FALSE", "ON" or "OFF" and ultimately the abstract "1" or "0".

Logic gates on the other hand are operators. They perform some operation such as "NAND", "NOR", "XOR", "NOT". They have inputs and outputs.

My claim is that "YES" is a logic value, not any kind of logical operation.

Ergo, "YES Gate" is basically, totally wrong.

That is the famous Forrest Mims that has been quoted here. He is not stupid. He has a sense of humor. I can quite understand him using the idea of "YES gate" to introduce logic to beginners as a pedagogical aid. It's not intended seriously. Forrest and his books got a lot of people into careers in electronics and digital design.
• Posts: 11,905
This thread will be closed. The information on logic gates can be found on other forums such as
https://www.electronicshub.org/introduction-to-logic-gates/

These forums are to discuss Parallax products. There have been no questions as such.
This discussion has been closed.