Talk:RCA 1802

Timeline Conflict?

The article states that it was "introduced early in 1976". However, it also says it was used on the Viking Mars landers. These were launched in 1975 and probably needed to be based on plans that couldn't change much into the manufacturing stage. Thus, such a chip would probably have had to exist around 1973. And, I doubt NASA would base a billion-dollar probe on a prototype. Perhaps it was the 1801 chipset/model? Or perhaps it was designed around the 1801 chipset but switched to 1802 late in the project because the 1802 is compatible with the 1801 set. --Tablizer (talk) 05:11, 15 July 2008 (UTC)

I'm fixing it to 1974, based on http://jbayko.sasktelwebsite.net/cpu2.html#Sec2Part1 and Microprocessor Report, August 5, 1996, Volume 10, Number 10. --IMneme (talk) 01:17, 19 December 2010 (UTC)

Note that it was NOT used in the Viking. This has been corrected with citations.--WillBo (talk) 08:15, 17 October 2016 (UTC)

Origins

old RCA semi manual has cd4057 cmos logic chips that implemented a 4-bit register/alu slice.

cosmac elf kit dates back to 1975. Key to space is SOS or silicon-on-saphire, which reduces latch-up on radiation exposure.

Shjacks45 (talk) 11:03, 23 August 2008 (UTC)

CPU architecture infobox?

Would be a nice addition, since the 1802 instruction set was mentioned in the Popular Electronic article as having been designed by a single person.. —Preceding unsigned comment added by Wikip rhyre (talk • contribs) 12:43, 11 March 2010 (UTC)

1802 in Voyager craft

According to the official Voyager2 Twitter feed, the processor used in the Voyager craft are actually based on the 1802 203.56.250.55 (talk) 23:34, 19 May 2010 (UTC)

If so, NASA has forgotten their own history, and is relying on unreliable web sources such as the earlier versions of the Wikipedia 1802 and Voyager program pages. The actual NASA technical reports on the Voyager describe the computer as a slightly updated version of the Viking orbiter computer, and the NASA technical reports on Viking describe the processor as something MUCH different than an 1802. The 1802 wasn't even announced, much less shipping, when the Viking was designed. The references to these NASA reports are on the Viking program and Voyager program pages. --Brouhaha (talk) 20:33, 13 September 2010 (UTC)

This has been correctly referenced and mentioned on the page, with citations, as well as having been corrected across the Internet where possible by several 1802 enthusiasts, although there are places where it cannot be corrected. (old articles, etc.) --WillBo (talk) —Preceding undated comment added 20:13, 12 January 2017 (UTC)

Complementary Silicon/Metal-oxide Semiconductor?

Complementary Silicon/Metal-oxide Semiconductor would be abbreviated COSMOS, not COSMAC. That's how it's bolded in the article, too. Does the acronym really stand for something else? 69.54.60.34 (talk) 17:57, 13 September 2010 (UTC)

COSMOS was RCA's acronym for their general CMOS process, not specifically the 1802. COSMAC was the acronym for the 1802 family. --Brouhaha (talk) 17:08, 2 November 2010 (UTC)

Undefined Instruction

I recall that in a computer I built around the 1802 in 1977 that the undefined instruction hex code 68 was essentially "lethal" to code it RAM. It wrote 68 hex over the next instruction. When the next instruction was executed the process repeated filling RAM with 68 Hex. This would be worth mentioning if someone can confirm my recollection. — Preceding unsigned comment added by 173.212.187.148 (talk) 18:30, 26 August 2015 (UTC)

The 68 hex instruction is "undefined" for the 1802, and used for extended instruction set instructions for 1804, 1805, & 1806. I have seen discussions about what happens when the instruction is executed in the 1802, which I think is as mentioned above, but it is unknown if that is universal for all (several) source company microprocessor chips. It is not "lethal", however. --WillBo (talk) 20:04, 12 January 2017 (UTC)

Package Markings

None of the chip markings/suffixes have any citations documenting. Citation Needed markings applied. If you have documentation, please cite. Encyclopedic content must be verifiable per Wikipedia standards. — Preceding unsigned comment added by 169.252.4.21 (talk) 08:27, 14 October 2016 (UTC)

Much of the information in this section was gathered from MANY source documents, so citing is problematic. I am in the process of creating a web page about this information on my website ( http://www.MDCCCII.com/ ), and will end up using it as the citation. It will have citations for its information. That should be good enough. I did find a decent citation for the second request, so I added that. I'm about as close to an expert on the 1802 as anyone can be, and I assure you I only add information to this page that I KNOW is correct. MOST of the citations on the page (and associated information) were added by me. I don't know when I will get my 'summary' page completed. But hopefully not too far in the future. It's a lot of work to do it well and right. (just compiling the information in this section was a lot of work) I only added this section because someone added some scant similar information in the wrong place, so I deleted it and added this more expansive information, knowing that I didn't have a citation for it yet. — Preceding unsigned comment added by WillBo (talk • contribs) 07:54, 17 October 2016 (UTC)

Citations

Someone went through and added "citation needed" in many of the sections, and multiple paragraphs within sections. Most of these can point to the same document (particularly those in the "Technical Description" section), the "User Manual for the CDP1802 COSMAC Microprocessor" (MPM-201x), an online copy of which can be found here:

https://archive.org/details/bitsavers_rca1802MPMualNov77_10819092

So that is the citation I intend to use. I don't know if I should add this citation to every paragraph, or only the first paragraph of the section, or only the last paragraph of the section.

Note that there is a Reference #39, "User Manual for the CDP1802 COSMAC Microprocessor", but that is all it has, no link to the actual document. It is used once in the article. I didn't add that, and I don't know if it is valid or not to do it that way.

— Preceding unsigned comment added by WillBo (talk • contribs) 08:07, 17 October 2016 (UTC)

Better Die Shot

Here is a better die shot than the one used in this page. I'm not sure how the copyright works here, is it possible to use this? Illiteration (talk) 15:19, 12 January 2017 (UTC)

Afaik, it has to be either in the public domain or the copyright owner has to give permission. --WillBo (talk) 19:57, 12 January 2017 (UTC)

Another application

The 1802 was used in underwater equipment deployed in the lagoon at Kwajalein (the downrange end of the Pacific Missile Test Range). The equipment detected the acoustic signature of a warhead strike on the ocean surface, recorded an accurate timestamp, and later reported its results by acoustic telemetry. We probably cannot document this because the source material is likely classified if it still exists at all (this was back in the 80s). But it was an interesting application. N.B. - I have never held a security clearance of any type. — Preceding unsigned comment added by 50.43.56.108 (talk) 02:12, 18 June 2017 (UTC)

where I saw chip X

After a few instances, a list of things that used chip X is no longer illuminating for an article about chip X. It woudl be much more worth while to say *why* X was used, what the alternatives were at the time, and show the particular advantages chip X had in that application. --Wtshymanski (talk) 17:51, 16 September 2017 (UTC)

I disagree. Historical information is ALWAYS valid and of value. It gives the reader a clear insight into how extensive the use of the CPU was, and documents and archives that important information. ALSO, some of the changes you made where you removed valuable information was tantamount to vandalism. I did A LOT of work on this article and spent MANY hours gathering and verifying this information. I don't appreciate you 'savaging' that work. MANY of the changes you made were COMPLETELY arbitrary and unnecessary and not only did NOT make the article better, but weakened and lessened it. It really deserves an UNDO. --WillBo (talk) 18:24, 16 September 2017 (UTC)

As I said above, a list of primary references to uses of X is no more than a clipping service. Some analysis of *why* this processor was chosen would be of far more value to an encyclopedia article. --Wtshymanski (talk) 19:03, 16 September 2017 (UTC)

You simply do not know what you are talking about. Your shoddy "editing" of the article information and deletion and removal of valuable information suggests that you should be banned from editing this article before you do even more damage than you have already done. --WillBo (talk) 19:38, 18 September 2017 (UTC)

This is deletionist nonsense. Suppose the benefits of having this information here are insignificant. What, then, are the benefits of removing it? What are the negative side effects of having information most people don't care about? Is it really that hard to scroll past something? Sure, you could find some far-fetched reason why unimportant information could be inconvenient, but the reasons why the lack thereof would be inconvenient far outweigh that, considering the incredibly small inconvenience it causes.

I personally find it interesting, so I'd rather it be kept, and the article's already pretty long so it's not a massive inconvenience. If you think that the article needs an explanation of why the chip was used in those applications, you can do the research and add it yourself, or at least try to convince others that it's important to do so, but removing a bunch of interesting historical information doesn't seem useful to me.

It seems that most of your edits are removals, so the issue is clearly bigger than this article. You ought to really consider who's adding more to Wikipedia; you, rapidly removing information and making everything more brief, or somebody focusing more on adding things. A lot of your revisions (going back a long time, I think) seem to remove actual information for the sake of brevity, claiming things are irrelevant or redundant when they clearly aren't, or that it's just so inconvenient to scroll past something for 1 second. I know that it's hard to go back on a general stance you've had for years, and not all removals are bad, but you should try to be less enthusiastic about deleting others' work. Illiteration (talk) 17:12, 22 September 2017 (UTC)

Wikipedia has infinite space and budget, but human readers looking at an article will die in only 70 or 80 years or so - an article that wastes human lifespan by being too long should be edited. You'll have to clarify what you mean by "most of my edits" - do you have a time span in mind, or over the whole 13 years? I do delete a lot of vandalism. I've no idea what the red numbers and green numbers sum to over the years. It might even be near zero? In the last 500 edits I count about 322 green edits, adding text. I don't know how zero net byte change edits rank me on your scale of evil. But that is not "mostly" deletions. --Wtshymanski (talk) 18:50, 22 September 2017 (UTC)