6502.org Forum  Projects  Code  Documents  Tools  Forum
It is currently Thu May 16, 2024 11:23 am

All times are UTC




Post new topic Reply to topic  [ 2 posts ] 
Author Message
PostPosted: Sat Aug 23, 2003 11:30 pm 
Offline

Joined: Sat Aug 23, 2003 11:19 pm
Posts: 1
Location: uk
Okay

Im daft - an open admission, but if anyone can advise on this I'd be dead greatfull.

But - in simple terms, can you simply exchange an existing 6502 NMOS processor with a 65C CMOS processor - without changing any of the other hardware ?

I want the 102 variant because of the extended instruction set (PHX and PHY and those other Branch instructions should have been conceived originally in my mind).

Hey better still - is there and NMOS "102" variant - that runs at 2Mhz - even better!!

Thanks in advance

Phil


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Sun Aug 24, 2003 7:04 am 
Offline
User avatar

Joined: Fri Aug 30, 2002 1:09 am
Posts: 8437
Location: Southern California
> can you simply exchange an existing 6502 NMOS processor with a 65C
> CMOS processor - without changing any of the other hardware ?

Since you want the simple-terms answer, it is that in most cases, it's no problem.

> I want the 102 variant because of the extended instruction set (PHX and
> PHY and those other Branch instructions should have been conceived
> originally in my mind).

WDC's 65c02 has all those instructions and more, and has the extra bus signals that California Micro Devices' G65SC102 had also. Mike Naberezny has them in stock and you can buy them from him on this website.

If you want more instructions though, for only another dollar or so you might as well go for the 65816, which permits you (but does not force you) to use 16-bit A, X, Y, and S, move the direct page around instead of requiring that it be zero page, and use a 24-bit address space, and has instructions to facilitate code relocation, block memory moves, multitasking, etc.. You get a lot more bang for the buck. To reduce the intimidation factor, you can initially treat it like a 6502, and begin using new features gradually as you learn them.

Of course I should point out that the '816 definitely will not work in a socket intended for the '02. The changes are few however, so you could make a board with a few jumpers to select which uP you'll be plugging in, so the same board could be used for either one.

> Hey better still - is there and NMOS "102" variant - that runs at 2Mhz - > even better!!

I think all the WDC 65c02's made now will run at 14MHz minimum, and typically more. The 2MHz days are gone.

Garth


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 4 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to: