Talk:MOS Technology 6502/Archives/2021

Primary source
A huge amount of the detail in the "History and Use" section comes from a primary source -- a YouTube video interview with Chuck Peddle. The Wiki policy on primary sources allows their use, but only sparingly; no synthesizing or interpretations based on those sources should be done, otherwise that strays into WP:OR territory. Since so much of this section relies on a single primary source, anyone who wants to work on this article should, instead of expanding it or adding more detail, try and find reliable secondary sources which can back up or correlate what was said in that interview, if possible. A lot of the detail in this section straddles the line between straightforward facts (which *can* use primary sources as citations) and analysis/interpretation of what Peddle is saying (which is *not* allowed). I don't feel the issue is so egregious as to warrant any removal of material right now, but I do think efforts on this article should be focused primarily on getting rid of the dependence on primary sources as much as possible.

I don't want to throw a bunch of tags in the article as that would make it look quite messy, so I decided to just post this here on the talk page instead. If I find time in the near future, I'll get to work on this. In the meantime I encourage anyone looking at working on this page to search carefully for quality secondary sources.  M r A urelius R  Talk! 03:47, 1 December 2020 (UTC)


 * I believe you are incorrectly interpreting why primary sources need to be examined carefully. The issue with primary sources is not simply who made them, but when they were made. The operational definition in this case is:
 * A primary source was a source that was created at about the same time as the event, regardless of the source's contents.
 * The concern is that someone writing about events that happened to them as they happened will not be an accurate reflection of those events or maybe deliberately obscuring them. The section on "How to classify a source" clearly spells this out.
 * Consider, for instance, if this was an article by Chuck when the 6502 was released and it contained statements like "Best processor ever!" In that case, one might be sceptical of its accuracy. But here we're talking about statements made decades later, surrounded by incredible historical detail, lacking any sign of obfuscation that I can see.
 * I do not see an attempt to examine this source critically, simply "primary bad". So do so, examine the source carefully. Do you see any reason to believe it is not an accurate account of the events, other than "primary bad"? If so, we have something to talk about. Maury Markowitz (talk) 14:21, 3 February 2021 (UTC)


 * The issue is that it's a YouTube video, which are discourages as sources (as far as I understand it) and also, it's just one person talking about their memory of events. There is no way to verify that what Chuck is saying is accurate. This is why secondary sources, which have researched & verified his statements, are so important. Anyone can say anything on any social media or video platform. I'm not doubting Chuck's integrity or memories; but having this entire section be based on *one person's account* of what happened over 35 years ago isn't exactly the shining definition of reliable sourcing.  M r A urelius R   Talk! 19:26, 4 February 2021 (UTC)


 * Feel free to add more sources when you find them. Maury Markowitz (talk)

Section "Moving to NMOS" implies that the 6502's competitors were PMOS chips. Actually they were enhancement-load NMOS.
(Pinging Maury Markowitz because he wrote the text involved.) This whole section, describing some of the semiconductor advances in the 6502, implies that the 6502's competitors, including the Intel 8080 and Motorola 6800, were PMOS microprocessors. This is incorrect—both were NMOS chips. (Intel used PMOS for its 4004, 8008, and 4040.) The difference is that the 8080 and 6800 used enhancement-load NMOS rather than the depletion-load NMOS used in the 6502. The multiple voltages given, +12V, +5V, and -5V, are characteristic of enhancement-load NMOS rather than PMOS. Intel's PMOS chips used +5V and -10V.

I'm not doubting that MOS Technology's existing fabs were PMOS, by the way.

--Colin Douglas Howell (talk) 05:22, 3 February 2021 (UTC)


 * You are correct, the change was to depletion mode NMPS, which I have mentioned in the 6800 rewrites. I only came across this detail after making the edits to this article. However, I am not convinced that MOS used PMOS and hadn't already moved to non-depletion NMOS. Maury Markowitz (talk) 14:04, 3 February 2021 (UTC)

Number of transistors?
The article states (in the infobox) that the 6502 had 3510 transistors. This seems to hide an important detail:

"The 6502 chip is made up of 4528 transistors (3510 enhancement transistors and 1018 depletion pullup transistors)."

This is mentioned even in the references quoted, like this amazing work of art.

I think this should be mentioned in the infobox. They are transistors on the die, and therefore need to be mentioned in a count. However, they are not "logic transistors". Should this simply be noted on a separate line in the box? Maury Markowitz (talk) 11:44, 12 May 2021 (UTC)