Is (WDC)Western Design Center 6502 the same with Motorola 6502?Both instruction and package?

> Is (WDC)Western Design Center 6502 the same with Motorola 6502?
> Both instruction and package?

I doubt it. I did some Googling and found noting. OK, some sites mention a Motorola 6502 but I think that is a typo.

A fact is that MOS created the 6500 as a pin compatible 6800, something Motorola didn't like at all. They forced MOS to alter the pinouts and the 6502 was born. With this in mind I cannot imagine Motorola producing a CPU based on a design of their arch enemy.

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The 6502 was a big enemy of Motorola. But whatever brand you're looking at, if it doesn't at least have a "C" (for CMOS) between "65" and "02", it definitely falls way short of WDC's. The CMOS 65c02 not only consumed a lot less power (and ran cooler) than the old NMOS ones that probably have not been made in 15-20 years, but also had all the NMOS bugs fixed, and added more instructions and addressing modes. WDC's 65c02 has further improved on that with more instructions and addressing modes, and added some more signals at the pins, namely ML\ (memory lock) output (pin 5 on a DIP), BE (bus enable) input (pin 36 on a DIP), and VP\ (vector pull) output (pin 1 on a DIP). They also made the RDY line bidirectional. These signal additions facilitate DMA, multiprocessing, and hardware interrupt prioritizing. Stopping the processor to save more power when nothing needs attention is now more practical than it was with earlier CMOS ones, whereas the NMOS 6502 could not be stopped at all. WDC's 65c02's are guaranteed to work at least to 14MHz.

Edit, over 14 years later: I posted an article summarizing the many differences between the CMOS and NMOS 6502, at http://wilsonminesco.com/NMOS-CMOSdif/

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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?

Motorola has never made a 6502. The references to "Motorola 6502" are all mistakes.

The original 6501 was pin compatible with the 6800, but Motorola harassed MOS Technology, so they changed the pinout and created the 6502, from what I heard. That's why Vcc and GND are in such weird places.

Toshi

Excerpt from DTACK GROUNDED #27, January 1984

Chuck Peddle headed the CPU design team which designed the 6800 at Motorola. Motorola had DIFFERENT design teams working on the various peripheral chips such as the 6820, 6850 etc. After the 6800 design was completed and checked out, Motorola did NOT reassign Chuck and his team to one of the peripheral chips.

Now is the time to recall a couple of aphorisms: "the Devil makes work for idle hands," and our own "there are some things which should never be done for the first time," such as design a microprocessor. The 6800 was Chuck's - and his design group's - FIRST microprocessor. And Motorola did NOT reassign Chuck and his design group to other duties, as we just said. Chuck did the obvious: he and his design team came up with a SECOND microprocessor design which was similar to the 6800 but corrected its most glaring deficiency: only one index register. Chuck and his design group also designed the microprocessor to be more producible. At this time the 8080 and 6800 both cost in the neighborhood of $360. Yes, three hundred sixty dollars. And Intel would not sell you an 8080 unless you purchased your DRAM from them as well.

So Chuck took his new CPU design to Motorola management and they had no interest whatever. "Chuck," they said, "we already have one microprocessor. We do not need two."

Consider how Chuck and the design group he led must have felt at this point. Motorola had failed to assign them useful work. They had designed a SECOND 8-bit microprocessor which, predictably, was in fact superior to their FIRST design. We suspect that Chuck and his design group felt rejected and unwanted. Certainly their new design seemed to be unwanted by Motorola. AND - (we emphasize this) - Motorola continued to fail to find meaningful work for Chuck's design group.

The predictable happened. Chuck (he was the leader of the group, no?) shopped around the semiconductor industry for a home for his group and for their new, superior, microprocessor design. He found willing takers at MOS Technology, a firm which at that time was specializing in calculator chips - sort of low-grade microprocessors, mostly (all?) 4 bits.

ETHICS. The semiconductor industry then (and now) featured easy nobility between employers. This has considerably benefited the industry and the industry's customers. But there is some ambivalence: it is O.K. for Bob Noyce to jump ship from Shockley to Fairchild and later from Fairchild to Intel, but if an employee of Bob's does the same thing then the employee is disloyal, traitorous and a possible lawsuit target.

But it is generally agreed that one should not take engineering drawings from ones' previous employer to the NEW employer. That is not just unethical but also illegal. Did Chuck carry engineering prints (what the aircraft industry calls "blueprints") of his new design to MOS Technology? We dunno.

What we DO know is that A) MOS Technology brought out the 6502 in a remarkably short time after Chuck and his team joined them, and B) Motorola brought suit against MOS Technology on the grounds that engineering drawings had been taken from Motorola, and won a court judgement of $300,000 from MOS Tech. (It appears that SOMEBODY carried those prints.)

We must recall that MOS Technology was a very small operation with limited financial resources (it is difficult to recall how much this industry has grown since those days). That $300,000 hurt them, badly. They had to look around for what is called these days a "White Knight", or friendly corporate takeover. They found one: Commodore and kindly Uncle Jack.

The rest of the story is well known. Chuck talked Trameil into coming out with the original PET 2001. Lots has happened since then including the weekend when Chuck and Bill Geiler designed the VIC-20; the brief time when Chuck left Commodore to be a consultant for Apple and then promptly left Apple and rejoined Commodore, presumably ladened down with Apple's secrets. Apple's anger shortly turned to laughter as Chuck broke off from Commodore and established Sirius Systems (later Victor Technology) and set out to become the head of the third largest computer company in the world.

But you should not believe that the 6502 was designed at MOS Tech. It was in fact designed at Motorola. Honest.

Yes, but Motorola never manufactured it.

Toshi