In my Dapple ][ project it looks like I may need to add support for the 65802 CPU in order to run the Apple //c+ ROM set. I am STFW right now for info on the '802, but what matters most is the differences from the 65C02 which I already emulate (and possibly the 65SC02 which I also emulate).

Would anyone be willing to supply me with this info? Thx in advance.

-uso.
cl00less n00bie

Did you really mean the '802? That's essentially a 65816 on the inside that's mostly pinout- and timing-compatible with the 6502 on the outside. The main thing it lacks from the '816 is the ability to address a 16MB memory map. If you don't need the 65c02 RMB, SMB, BBS, and BBR instructions, you can use the '802 to run '02 code. I'd recommend using the forum search feature for "816" and you'll find lots of information that has already been posted. The '816 has 16-bit registers and a lot of capabilities the '02 does not have. WDC's website has the data sheet, and their excellent programming manual has all the information you need to start programming. This manual is very clear and complete. You definitely need to get it if you're writing a simulator.

Garth

I think so. Most sources say the //c+ used an '802, and when I take and plug the //c+ ROM into Dapple ][ or ApplePC as a standard //c I get the string "Apple IIc +" followed by a series of beeps and register dumps and stars. A quick look at the code seems to suggest '802 opcodes are used in the ROM.

I see a lot of info here and there on the '816 but nothing of use about the '802 except that it's a cut-down '816 (and thus a superset of the 'C02 but incompatible with SC extensions). I will continue to look.

-uso.

Well it's not "cut down" very much. It still has all 255 op codes, although the '802 has little use for the op codes with long addressing. I developed my '816 Forth on an '802, treating it just like an '816 with all memory and I/O in the first 64KB bank, using the portions of the programming manual that are specific to the '816. I'll just have to verify the operation of the words that handle data in other banks when I get my next workbench computer finished with a real '816. (I intentionally made all actual Forth code run in bank 0, since 64KB is a lot of memory for what is probably the most memory-thrifty language.)

Simply treat the '802 this way:
1. From a hardware point of view, it's a 65c02.
2. From a software point of view, it's an '816 sitting in a hardware design that ignores the bank address byte.

'816 pins that get left out on the '802 are VPA, VDA, M/X, BE, and ABORT\.
If it's in a DIP instead of a PLCC, then the VP\, ML\, and E are also left out.

I haven't found any '802 data sheets on this website or WDC's (since they discontinued it a few years ago). I guess I should send Mike Naberezny a copy to post. It sounds like what you really need is WDC's programming manual though. I am aware of another book (although I haven't read it), "65816/65802 Assembly Language Programming" by Michael Fischer and published by Osborne McGraw-Hill. I expect that it is out of print and harder to find, and I can't imagine that it's as well written as WDC's, which I'm sure will be printed and available for many more years.

Garth

My rationale may be flawed - it appears that the Apple //c+ has a stock 'C02 - but I still think an '802 might be interesting.

But I guess I won't be tacking an '802 emulator into the existing core, if it's got the full 16-bit mode...

Maybe I'll kludge away on M6502.

-uso.

Garth,

At the time that WDC supplied the datasheets that are currently posted on 6502.org, the 65C802 was out of production. If you would like to send me the datasheet I would be happy to post it for you.

Regards,
Mike

_________________
- Mike Naberezny (mike@naberezny.com) http://6502.org

I have emailed many times WDC asking for how to purchase their manual and in over 20 attempts to various email addresses (sales@, info@, and others they had available) I haven't got a single reply.

How do I go about purchasing the manual?


in the end, I locate a '85 version of a book of the same name used on Amazon (it has a note that WDC made it their official manual at some point). What I don't know, is if the difference between the original print run that I purchased (used) dated '85 is any different than the one on the WDC web site dated 2003 (with a diclaimer that they have "reproduction" rights). As well, I haven't been able to navigate to the book info on WDC directly, but had to pull up the link from a search on google that deep linked to it years ago (and it is still the same location).

Anyone know the differences or how I can get one directly from WDC? As well, when I inquired how to purchase their 6502/816 c compiler they didn't (as I've come to expect of them) but I saw from a post on a newgroups that it is about $10k or more?? Ouch. cc65 doesn't compile 65816 (or 16-bit code). All other options are prohibitevly expensive to purchase.


Thanks,
Shawn

They're terrible about answering E-mail. Just call them up on the phone with credit card in hand and say "I want to order the programming manual."

The date on mine is 1985 as well. It was expensive but a really good investment. I suppose all that's changed since '85 has been clock speed and power consumption, neither of which directly affect the programming manual.

Well, as I arrived to my home today there was the book. Dated '86, actually. Anyway, it looks as though it has never even been opened let alone used before. The (softcover) binding has a fresh "crack" when I opened it. Table of contents matches what they say online.

Thanks,
Shawn