I am trying to build a 6502 computer, and I am reading the primer. I have decided on these configurations

Specs
65c02 processor
32k ROM
16k RAM
20x4 LCD display
Simple Hex Keypad with a few command buttons
Expansion slots to add VGA, New Keyboard, etc. in the future

please tell me if this is way to complicated for a beginner even if I stick to it

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JMP $FFD2

If you are going to use a Hitachi compatible display them you must properly initialize the display, which is a bit tricky. The simplest way to go arround it is to use a ACIA chip, and use a PC as the terminal, or get some other type of display, or a some sort of display controller that can recieve raw ascii characters. A while ago I wrote a program for the 16f877 that made him a nice ps/2 and lcd controller, very simple to interface. But I didn't upload the code on my site.
If you want to use my chip as the solution, send me a pm, or you could use Daryl's text generator and interface your computer with a TV: http://sbc.rictor.org/vid3.html
He also has a proper LCD controller circuit: http://sbc.rictor.org/vid4.html

I have sample code on my website at http://wilsonminesco.com/6502primer/LCDcode.asm

What you want to do, at least before the video part, is not too big of a chunk to bite off. I discuss expansion buses and interfaces in the primer though at http://wilsonminesco.com/6502primer/ExpBusIntrfc.html . Take heed.

Video is not a simple thing, and near the bottom of http://wilsonminesco.com/6502primer/displays.html, I link to a couple of very small off-the-shelf video boards available that you could interface to, to make it a lot easier.

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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?

I don't know why you don't just go and get a Micro-KIM kit. It does everything you want. CPU, RAM, EPROM, hex display, keypad, expansion header, and serial interface. The only thing it lacks is that you don't get to design the actual schematic, make the part choices, or layout the board. You get to solder it together.

Don't like the KIM monitor? Make your own, burn it on the EPROM. The whole thing is eminently hackable.

But all of the chips are socketed, so when you want to move up and start laying circuits and such out, you'll already have a majority of the parts -- just yank them out of their sockets.

Not quite sure what you want to do, but I think it's a great starting point for someone that wants to dabble in this stuff, and see some early success. And bang for the buck, it's a steal.

That is like cheating.
IMO, it is always more fun to build stuff from scratch, also you learn more.

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

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

Really? I guess learning soldering techniques, parts identification, parts placement, how the chips in the board relate to the schematic, circuit testing when things inevitably go awry. That's not learning anything.

Actually having a running system to practice his 6502 assembly skills, interfacing hardware, doing experiments. That's not useful at all.

Having a shortened time of development, a reduced tool chain, lower costs overall to the first glowing LED of success. Not helpful whatsoever.

When he's done he'll have a working system and a working schematic. He'll have most of the parts as well. He can take the schematic as given and duplicate in his medium of choice (bread board, wire wrap, PC board) and get that working with the knowledge that the underlying foundation is solid. By the time he gets to this point, he'll find he actually enjoys the process. Because truth be told, he may not. It just may not suit him.

You've already told him that what he wants, even if he "sticks to it", it too much for a beginner. This jumpstarts that and lets him dabble in all of the elements. He can trace and understand the design without actually doing it, because he'll have functioning hardware to poke at. You're right, that's a complete waste of time too.

Better to just get random bag of parts, a large tool chain of components (not just a soldering iron and a VMM, but a EPROM burner, software, cables, plus likely a scope BEFORE HE'S BOUGHT HIS FIRST RESISTOR). Better to learn all of that all at once, have all of those dependencies out the gate, than to incrementally work your way in to it going from success to success.

Yup, you've talked me in to it. This was a silly idea. What was I thinking.

My only complaint about the Micro-KIM manual is that it does not have a staged assembly path much like Ciarcia does in his Z80 book. That would make it even more useful, IMHO.

Hey, how about we stop with the negativity? By all means make a constructive comment about scope reduction, but it's about time our regulars had understood that there are several different reasons for getting into a 6502 project and therefore several different valid ways of proceeding.

Better yet, if you have a negative comment to make, just wait a day or two and perhaps someone else will have picked up the thread with a more constructive approach.

Cheers
Ed

It seems that these are two completely different approaches, both totally valid.

-Design and build your own hardware from discrete chips. This is completely fun. You will in fact learn how to debug hardware, solder, make terrible make-shift connections that stop working until you realize you shouldn't etc. There is a lot of room for stupid errors and complete failure. Or it may just work and you learn very little other than being neat and organized saves a lot of time and effort. By the time you get the LED blinking, you may want to make a bigger computer with more RAM or a '16. That's because you like to tinker with hardware.

-Get an off-the shelf working board. Maybe mess with the hardware, maybe not. That is because you like the software side more. Maybe you don't like spending days trying to figure out what part of your circuit is overheating or look for that broken wire. Maybe you would much rather spend time debugging deadlocks in interrupt code and thinking about an OS or graphics code.

There is also the retro angle. Working with exact chips of the past, or emulating them. Then there are emulators. And FPGAs. There is nothing wrong with any approach, and there is no 'cheating'. Whatever you do, is better than doing nothing.

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In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut