Correct 6502 for an Apple II Rev 0?

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Correct 6502 for an Apple II Rev 0?

Does anyone know what the correct 6502 for an original Apple II Rev 0 is? Is it just a black plastic MOS 6502 with date code for 1977? Did they ship any Rev 0's with white 6502's?

Thanks!

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Re: Correct 6502 for an Apple II Rev 0?

Well Serial #2 Apple II has a black 6502 and it doesn't look replaced.

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Re: Correct 6502 for an Apple II Rev 0?

Well Serial #2 Apple II has a black 6502 and it doesn't look replaced.

Thanks.

Are there pictures available of this Apple II online? Also, how can you tell if it's been replaced?

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Re: Correct 6502 for an Apple II Rev 0?

Knowing Corey's Reputation, he might have had, "Hands On" , Serial #2...

MarkO

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Re: Correct 6502 for an Apple II Rev 0?

Here's a pic I took of #92.
https://drive.google.com/file/d/0B9r6vH-4NK4NS3BHM1dPU204Qzg/view?usp=sharing

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Re: Correct 6502 for an Apple II Rev 0?

Here's a pic I took of #92.
https://drive.google.com/file/d/0B9r6vH-4NK4NS3BHM1dPU204Qzg/view?usp=sharing

Thanks!

That brings up something I'm noticing. A disproportionate number of the old 6502 chips I see pictures of seem to be Synerteks, not MOS like I would have expected. Were Synerteks more common as original equipment in the early Apple II's?

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Re: Correct 6502 for an Apple II Rev 0?

I have to go though my pics of #2 but I think you are right on the very early ones. They weren't MOS chips.

I just checked another sub 100 and its synertek.

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Re: Correct 6502 for an Apple II Rev 0?

I have to go though my pics of #2 but I think you are right on the very early ones. They weren't MOS chips.

I just checked another sub 100 and its synertek.

Cool.

I wonder if it had to do with Commodore owning MOS by then, and Apple didn't want it's success to provide business to one of it's competitors.

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Re: Correct 6502 for an Apple II Rev 0?

I have to go though my pics of #2 but I think you are right on the very early ones. They weren't MOS chips.

I just checked another sub 100 and its synertek.

Cool.

I wonder if it had to do with Commodore owning MOS by then, and Apple didn't want it's success to provide business to one of it's competitors.

Woz got his original 6502 from Chuck Peddle, but later didn't want to deal with Commodore so bought from Synertek and Rockwell...

IIRC, Jobs tried to get Commodore to buy Apple, and hire Jobs and Woz, but Commodore wouldn't do it... That probably has something to do with it...

MarkO

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Re: Correct 6502 for an Apple II Rev 0?

I believe from the start all production Apple II boards had Synertek 6502 CPUs installed. The earliest bare-board systems (an option for customers who would supply their own PSU & keyboard ala Apple 1) had white ceramic SY6502 chips. There were around 200 bare boards sold this way from April-May 1977, but l'm not sure if the white ceramic 6502 were still being used by the time complete Apple II systems w/ case, keyboard and A2M001 PSU began shipping in June 1977. Regarding Jef Raskin's serial #2 computer, I don't know how one can be sure with any certainty that the black 6502 is original, because how can you tell? Consider also that serial #48 that sold on eBay back in 2013 clearly had a white ceramic SY6502 in the identical IC package as seen on the earliest boards, so to me it seems more likely that the earliest complete A2S1-numbered computers had white 6502s and this changed within the first 100 units to the black chips.

Howie

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Re: Correct 6502 for an Apple II Rev 0?

Does anyone know what the correct 6502 for an original Apple II Rev 0 is? Is it just a black plastic MOS 6502 with date code for 1977? Did they ship any Rev 0's with white 6502's?

Thanks!

I wast wondering about this myself too. So far, all of the Apple II board pictures I saw online were using Synertek.

Here's a #133: http://ca.meron.cc/post/apple-ii-serial-133/

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Re: Correct 6502 for an Apple II Rev 0?

In fact, I've seen only one early Apple II rev 0 with a white ceramic 6502 : A2S1-0047, motherboard 1-243, no vent on case.
It was sold on eBay on June 2013 for a whopping 23099$
Here are the pics.

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Re: Correct 6502 for an Apple II Rev 0?

In fact, I've seen only one early Apple II rev 0 with a white ceramic 6502 : A2S1-0047, motherboard 1-243, no vent on case.
It was sold on eBay on June 2013 for a whopping 23099$
Here are the pics.

Oh, yes that was the system I was thinking of in my post above: serial number 0047, not 0048 as I mistakenly wrote. I am aware of two Apple II bare boards that were sold in early 1977 before the cases/keyboards/PSU were ready and they have the identical white SY6502 chips with the gold grounding strap and two dots just like the one in that eBay auction.

Re: that link to photos of board #133 with the black 6502, you'll notice the date stamp on the chip is 7803, so clearly that wasn't the original chip the board came with.

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Re: Correct 6502 for an Apple II Rev 0?

Sherlock's Apple II has a board date of 2278, (I sold him the machine so I'm extremely familiar with it Smile
so any 6502 prior to that would be appropriate. The CPU had been replaced by the previous owner (previous to me) and I did not have an older 6502 at the time.

My personal Apple II from childhood ( s/n 3283) had a Rev 0 board date of 5578 and had a black Synertek with a date code of 7804.

I'm still trying to find Sherlock an older 6502 that is date correct but my current supply stops in the early 1979 range.
Zan

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Re: Correct 6502 for an Apple II Rev 0?

I wonder if the early boards had the white synertek and then people like Raskin changed to the plastic ones because of the RoR bug, though I don't know if the Synertek had the same bug as the MOS.

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Re: Correct 6502 for an Apple II Rev 0?


My personal Apple II from childhood ( s/n 3283) had a Rev 0 board date of 5578 and had a black Synertek with a date code of 7804.
Zan

Actually, all rev.0 boards were made before they started using the 4-digit year/week numbering system, so the 5578 on your board was its serial number. Makes you appreciate back then production remained modest enough that it still seemed practical to individually number each one!

I wonder if the early boards had the white synertek and then people like Raskin changed to the plastic ones because of the RoR bug, though I don't know if the Synertek had the same bug as the MOS.

I'm 100% sure that by the time Apple II were made the RoR bug in 6502 was history. Only late 1975 chips had the bug - by early 1976 the bug was fixed. The earliest Apple II boards had SY6502 with date codes around 7702 (or to be technically correct they were printed as 0277). Raskin may have swapped out his 6502 for any number of reasons - failure, "borrowing" the CPU for another project, etc.

Howie

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Re: Correct 6502 for an Apple II Rev 0?

Howie,

I didn't remember when the 6502 fixed the bug. I just knew you can't use Mike Willegal's original memory test program on a real A-1 because of the RoR bug. I wrote my own. I think Mike fixed it at some point also.

Cheers,
Corey

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