You can look in the Apple II manuals. I don't remember anymore if that's where I got the info. You can find lots of Apple II information linked on my links page, at http://wilsonminesco.com/links.html#brands . This section has various brands of computers in alphabetical order, so Acorn is first, then AIM-65, then Apple.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Doesn't help any unless you can name the book as there
are countless books for the Apple II.

What about this diagram?
This is an updated version of the 6502 CPU.

It was decapped, photo taken and block
diagram drawn.

Can anyone read this?

muchtolearn: that's Donald Hanson's well-known diagram. Follow the breadcrumbs and it will lead you to Michael Steil's blog, and repository, and talks on YouTube. It will also lead you to the visual6502 wiki.

Any web search engine will get you from any of the phrases you are quoting to the source material. You should follow those breadcrumbs too, and do some reading.

It's very easy to ask a question, somewhat more difficult to answer one. If you keep asking questions without doing any work, you use up the goodwill that you start out with. Don't be the house guest who never helps with the washing up.

Big Ed

Any web search engine will get you from any of the phrases
are quoting to the source material. You should follow those bread crumbs too, and do some reading.

Making an assumption of what you think
I am doing has lead you to errors. In my last post I did not receive any answer
then I remembered that Ken Sherriff had de-capped a 6502 and
Take a die photo. So I emailed him asking if thee was an updated schematic and he
gave me the pagetable.com link. Hence the block diagram I uploaded. Which leads to you comment about hence do some reading. I read quite a lot and have read many books of 6502, computers and assembly language. if the block diagram is more upto date then books written in 70's and 80's, then it makes it more informative. Gee, I don't know, we might learn some new information or get clarification of what had been written or missing parts we didn't know about the CPU filled in.

I am finding bloqs and websites more informative today about topics already written about provide greater clarity with examples. That's the great part about the Internet you interact with it. With a book
You just read it and comprehend what the author is saying . (well try to anyway as some books don't do that very well or at all).

As an example. I wanted to know more ISR. I knew how interrupts worked
But not ISR. Then I found a bloq that did this. Better than any book I had read on the subject.
It was clear, detailed and had examples. (If you want the bloq name just google
Atarilynxdeveloper.wordpress.com - chapter 17 interrupts)

it's very easy to ask a question, somewhat more difficult to answer one.
I agree. if you don't know then say so. There are many reasons to keep asking
The same queestions. You do not know and would like it explained. You have read about it but it is not clear that what you read and need further clarification on a particular part or parts or the entire concept.

As for don't be the house quest who never helps with the washing up, I don't live with you so I don't need to share you chores.Maybe you should look into hiring a maid it is too much for you.
And this concept of follow the bread crumbs, I have never read that in all the books on computers I have read. Perhaps the maid can help with that one too.

muchtolearn, I'm trying to figure out some kind of pattern regarding the pieces you're missing. Much of my voluminous 6502 website which I started in 2012 was written to answer questions and misunderstandings that kept coming up on the forum. I spent many hundreds of hours trying to make things as clear as possible. There's more coming, and I keep updating the existing pages too, trying to make them more helpful. Sometimes we just have to suggest other books.

Regarding identifying a pattern: You indicated for example that you weren't sure what a bus even is, or what a port is. (Basically all I/O is through some sort of I/O port, and a computer with no I/O is pretty worthless.) Some of these things are much more important than the block diagram of the innards of the 6502. Such a diagram, or how the ALU is designed, or a die photo, could be important when you're ready to design such a processor, or extend or modify the design, or maybe even to write a simulator; but it's not important to learning how to build with the 6502, or to program it. You don't need that much internal detail for that any more than you need to understand the math involved in electromagnetism in order to change the alternator in a car. It is enough to know what the processor does, without much attention to how it does it internally, at least to start.

For building, use my 6502 primer. For starting programming, use the Eyes & Lichty programming manual. For understanding 6502 interrupts and how to service them and how they're used, use the 6502 interrupts primer. (All of these were linked earlier.) For understanding how things were done on particular vintage 6502 computers, refer to their reference manuals which are linked on my links page and on the websites of other members here. Rich Cini for example has hundreds of such scanned documents on his site. The non-forum part of this site, 6502.org, has a wealth of documents, scanned magazines, books, projects, source code, and other 6502 resources. Ed who posted above is kind of our documentation expert. He really knows how to find and link relevant online helps into discussions here. He is quite active on the AnyCPU forum too, where most of the traffic is about designing microprocessors.

One thing I might recommend is to go ahead and ask questions, but also be open to possible differences between what information you think you need next, and what might be a better next step, as perceived by someone who has had years of success in this field.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Sorry for my grumpiness muchtolearn. I woke up in the middle of the night.

It would help us a lot to know what you are trying to do. Some of the latest material you mention is about the internals of the 6502 and how it does what it does. That's very interesting to many of us, and very useful to the dozen or so people who are aiming to build their own CPU out of logic. But if you are trying to understand the next level out, the usual level, which is aiming to build your own system using a CPU chip which already works, I'd suggest you need a different level of information.



It would help greatly if you could use the forum's quoting mechanism! Please tell us more about this computer. Should I assume you are at college and using a trainer system or a dev board of some kind?

Yes. Put [quote] and [/quote] around the parts you're quoting. (Marking the quoted part as a block, then clicking "Quote" above the writing area does this too.)

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

A lot of people - including me - got started on other books. Rodnay Zaks' Programming the 6502 is a classic. It looks like Lance Leventhal also wrote one. I'm sure you can find a cheap secondhand copy, or a copy on line. The Advanced User Guide for Acorn's BBC Micro is also pretty good.



Indeed, asking questions is good: and there are good ways to ask questions. There's plenty of advice about this on the web, but this piece is a classic.

There's also a wealth of answers already out there: both this forum and stackoverflow can be very good, as well as the sites of many homebrew computer makers. See particularly this thread:
Best way to start learning 6502 Assembler
and the diagram within by Bob Sander-Cederlof.

In fact, Lance Leventhal wrote two 6502 books: 6502 Assembly Language Programming and 6502 Assembly Language Subroutines. The former is what I would consider to be the definitive work on the 6502 (and 65C02, in the second edition) and the latter a 6502 "cookbook" with many useful routines These are the two books I would recommend to anyone starting out with the 6502. I would also recommend the Eyes & Lichty programming manual, which is more up-to-date and focuses more on the WDC processors, which are the ones in current production.

As far as knowing exactly what is going on inside the microprocessor, take Garth's words to heart. I think most around here would consider me to be a 6502 family assembly language programming expert. Yet, I known little of what goes on deep inside the microprocessor. I don't need to know such details to write software and you don't as well. Unless you are planning to write a simulator or duplicate the 6502's function in programmable logic. I'd recommend that you direct your focus to the software aspects of the 6502. If you are interested in scratch-building a 6502 device then you will need knowledge about the MPU's hardware characteristics, such as the bus protocol, timing, etc. However, that still does not require intimate knowledge of the internal characteristics.

In any case, asking disjointed questions and acting peeved when they are not answered to your satisfaction is not how to get on the good side of forum members. Ed's analogy of a house guest who doesn't help around the house is apt and should be considered as you pepper us with questions that can mostly be answered with searches of both this site and the Internet at large.

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

Whether or not you believe it, BigEd has a very generous disposition and a well-deserved status here as one of the highest authorities on the subjects at hand. I have seen him become mildly annoyed a few times in the past, but those reactions were justly provoked, at least in my opinion, and this thread is no exception. His apology to you was polite but equally unnecessary (again, in my opinion).

BigDumbDinosaur, Dr Jefyll and Garth are brilliant sources of knowledge and hands-on experience, and are also very eager to share this knowledge (with a generous sprinkling of pedantry as an additional "bonus" in BDD's case ).

With all due respect, just a touch of humility on your part might turn out to be more help than hindrance, at least around here. Aggressive attitudes typically lead to alienation, and it would sadden me to see that happen yet again. Just sayin' ...

Mike B.

And now the descent has occurred.
Another post about manners and etiquette
but this thread is about "programming" (no its not that's
just a cover story to talk about mindless issues)
No answers have been given because I am
now at the conclusion that there are no answers.
Just point to other authors to who wrote books so long
ago they are from a by gone era.

I think you may not have explained what you wanted very clearly. Initially you said you wanted information about the 6502 architecture. That's a bit ambiguous, in that it could mean:
1) The architecture of a whole computer (How the CPU fits together with the other components).
It could also mean:
2) The architecture of the CPU (It's internal operations).
By the looks of it, BigEd thought you meant 1). If you're looking to build a system based around the 6502/65C02, then his answer was right on point, as was Garth's suggestion of the MOS Hardware Manual.

If you meant 2), then Garth's answer about Dieter's pages is probably on point.

If you're looking to write programs for a 6502-based system, then you don't really need to know how the guts of the chip work. I'm not saying you shouldn't or can't, just that is isn't necessary. You just need to know how to make the chip do its thing, and in that case, I would definitely recommend the Eyes & Lichty programming manual.

And: The fact that these books are old shouldn't be an issue; the 6502 is an old chip(one could even say it's also from a bygone age). Even with the 65C02 or the 65816, they haven't changed much in the past 20-odd years. The info in those old books is most likely still applicable.

There are answers. We have given you a few, in the form of pointers to where information may be found. If we give information and no reference, then it's probably considered common knowledge in this circle.
(Garth's comment about the apple II manual sounds like it's referring to the actual user/programmer manual produced by Apple for that machine, BTW.)

It may surprise you to learn that there is really very little about computing today that is new. Oh, there may be new algorithms and the occasional new language, along with such concepts as massively parallel computing, but most of the groundwork was done in the 1950s and 1960s, which predates the microprocessor. Even the Internet is old, closing in on 50 years.

Computers today are not much different than they were when I started out in the late 1960s. Mostly what has changed is the machines have gotten smaller, less power-hungry, less fragile, easier to use (relatively speaking) and a whole lot faster. The manner in which they operate hasn't changed so much that the writings of those authors from a "by gone (sic) era" are no longer relevant. Just as today's automobiles still have reciprocating engines and geared transmissions like their predecessors of 50 years ago, today's computers still have the elements of their predecessors of 50 years ago.

None of the currently-used microprocessors can be considered "new." The 6502 architecture dates to 1975. The Intel x86 architecture has been around since 1978. Ditto for the Motorola 68000 family. Even the advanced (for the time) 32 bit RISC architectures are at least 30 years old (e.g., ARM was first released in 1984), and the newer 64 bit RISC machines are pushing 25 years already.

It could be that reading those old books might infuse your mind with new knowledge. I suggest you look into it.

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

Point is, that the best and most detailed documentation about some piece of technology (especially microprocessors) usually is written
in the time frame when said technology was new and invented\released.

Could be, that quite a few of the authors that wrote books and articles about it _later_ just had used "copy and paste" without fully getting the context,
leaving away (or accidentally falsely interpreting) some important part of it.

So for seriously digging into the basics of how something works, I think the best is to get hands on some old books from a by gone era.
For getting started, I would suggest to take a look at Book 1 for the Elektor Junior computer.
It nicely explains the hardware of a 6502 computer, and the 6502 instruction set.


BTW: in the "good old days" when there was no internet, just a small technical book could give you enough "brain food" for a year.
When visiting a book shop nowaday and searching for technical books, the best you probably are able to buy is a book containing screenshots from the M$ windows online help.

ttlworks

Yes you have explained what is missing.
The books I have read were written in the mid 80's.
So that's almost 10 years after the CPU is released.

I am reading the Elektor Junior Computer Book 1.
This is great. It explains what I am wanted to know.

Thanks for providing a real answer.