The code already checks for 65816 by first checking for 65C02, and only then using XBA instructions to determine if it's a 65816. As for the SMB5 instruction, you are indeed correct; I've modified the comments to indicate that the detection finds "old" vs. "new" type 65C02 chips. Apparently some ...

I just spent a few hours researching some of the differences between 6500 family variants and writing a short piece of code that should be able to detect what kind of CPU you're running on top of. I've not tested it thoroughly! It works as expected on a C64 (result of $0c meaning normal NMOS 6502 ...

Also, is there a particular logic family that is best suited for these kinds of tasks? I'd rather not find out that I picked up the wrong one after I've already got it in hand...

So, correct me if I'm wrong, we're basically talking about having the caps as close as possible to flat-out piggybacking every IC that's in use. You said that most beginners completely ignore the rules of good design too; I was curious as to whether you had a moment to elaborate on that, beyond the ...

What kind of caps should I use for decoupling? Does it depend on the IC that I use?

This is AWESOME! You guys are the best. I'm getting excited! :)

My eventual goal is to start working on projects where I design a CPU from discrete logic, much like the infamous Magic-1 project. One thing I have a bit of trouble with is designing the circuits themselves, though; while I can easily ...

RadioShack is overpriced and doesn't sell 74xxx logic IC's, and I'm just now starting to get into hardware design and troubleshooting, and am currently building my workbench. I apparently am not so hot at finding electronic component suppliers that are non-bulk-order and aren't excessively costly ...

Well, I'm one of those people who sees things from many perspectives; I run a business, so I can see the business side of things where most of us tech-heads see only things like cool stuff that can be done with X, Y, and Z, or dream about the ideal and say "if only this worked like this!" I love to ...

The only problem with that is that it wouldn't be a 6502...it'd be a 6502 on steroids! :)

Unfortunately, we have to work with what we've been given.

Also, Contiki and LUnix LNG are nice semi-portable hobbyist operating systems, but they're not exactly "supported" or designed with embedded stuff in ...

Ruud, I don't think it would really be all that practical to ask everyone to toss out their ROMs in their old computers.

I am currently in the preliminary stages of planning out development of a cross-platform 6500-series-based OS which I intend to market and license (and yes, there will be ...

Yikes.

And why isn't this advice posted somewhere on this site? :)

Thanks for the help--I was starting to figure those things out on my own, in fact, but the jump-start is quite welcome, and I'd highl recommend someone get Mike to jam that info elsewhere on the site as a permanent document.

IIRC, POSIX relies on C, and C is simply not something that runs quite optimally on 65xx CPUs, no?

And I don't know much about POSIX anyway. My main problem with my prototype was that it simply didn't provide certain things I needed, and while tons and tons of it could be reused (I had malloc, some ...

It's times like this that I wish my OS hadn't proven to be so poorly written. I'm planning to do a rewrite from scratch with definite pre-planning and goals instead of just jumping in for educational purposes, and maybe when that's done it'll be more helpful.

I'm wondering if there are any 6502 emulators that use the Linux console instead of Windows or X11, etc. GUIs. I want to turn an old Pentium 133 into a 6502 development system, but don't want to use X11 to do it. I doubt it exists, but if there is one, I'm all ears.

Actually, the idea of running a PC natively from a virtual 6502 implementation would be a bit too exotic. You're talking about enumerating PCI devices, handling ACPI tables, running Ethernet adapters, babysitting USB devices, and more from a system that can only natively address 64K of space in ...