65802 anyone?

[barrym95838]

Raymond,

I can't recall the speed rating of the '802 I tested in my ][+ over 25 years ago (-4 maybe?), but I don't remember encountering any difficulties (other than lack of monitor support for the native mode, obviously). I wasn't using any peripherals with interrupts, or any DOS other than 3.3.

Mike B.

[BigEd]

Welcome Raymond!

It sounds like the CMOS CPU is likely to run well in an Apple II (I confess I don't have a good grasp of the various models or revisions of that machine.)

Some of you here might be interested to know that it's not so straightforward in Acorn's BBC Micro - there's a thread with experiments here where it's found that slugging the CPU clock with a capacitor, to skew it by 10-20ns, can rescue the situation. What's extremely unexpected is the failure mode: sometimes bad N or C flags from an SBC immediate, and no other addressing mode or instruction. The result is OK, but the flag not.

[ttlworks]

Welcome to the forum, Raymond.

DRAM timing, 65C02 too fast, tinkering with delaying the PHI0 clock input of the CPU to compensate for this...
Sounds familiar, somehow.

[handyandy]

Plamen now sells a plug-compatible 65816 for 6502 computers: http://www.a2heaven.com/webshop/index.p ... uct_id=151
His stock depletes often so if interested visit occasionally. As of now there are 3 available...

Cheers,
Andy

[Tor]

Out of stock now...

[rpiguy2]

Even before the IIgs folks were replacing their 65c02s with 65816s in the Apple IIe and IIc simply gain access to 16-bit wide registers. There were a couple of spreadsheets that could take advantage of the 65816 and the speed advantage was massive, even at 1mhz, just because it was so much easier to deal with 16-bit values when number crunching.

[LeoN]

http://www.pro-electr.net/search?q=w65c802

[GARTHWILSON]

LeoN wrote:

http://www.pro-electr.net/search?q=w65c802

If it's true, that would be be marvelous! Do they really have 10,000 real ones in stock?? It's in China, so it is suspect, because of all the fakes that have been coming out of there. According to this pie chart from Wikipedia, China produces nearly twice as many counterfeit products as all other countries combined:

It might be worth buying two or three, testing them, and if they prove to be legitimate 65802's buy more, and if it still looks good, buy a load of them to keep for people here and other 6502 forums.

[LeoN]

On the photo, the marking of chips is the same with that. And the production date stamp is the same. Probably non-faked chips.

[BigDumbDinosaur]

GARTHWILSON wrote:

LeoN wrote:

http://www.pro-electr.net/search?q=w65c802

If it's true, that would be be marvelous! Do they really have 10,000 real ones in stock?? It's in China, so it is suspect, because of all the fakes that have been coming out of there. It might be worth buying two or three, testing them, and if they prove to be legitimate 65802's buy more, and if it still looks good, buy a load of them to keep for people here and other 6502 forums.

I'd be amazed if they weren't fakes.

[BitWise]

LeoN wrote:

http://www.pro-electr.net/search?q=w65c802

Thats where mine came from and so far everyone i've tried has worked.

I might be tempted to get some more last time they only had 16.

[eightbitdoh]

Hi, Just an update years after the topic. While I never sourced an '802, I did replace my 6502 with WDC W65c02s in the A][ motherboard using the steps listed on the WDC site (jumper lead and pin left out of socket).

Back to topic I guess 65c802s were actually available last year - I'm getting errors on pro-electr.net site.

I have use of an expansion card with an '816 in it, so didn't pursue.
Raymond.