Talk:Serial port

Yost issues

I have noticed that there may be a couple of errors (before the edits I made) in the pinouts.

• The claim that Cisco uses Yost seems to be partially contradicted by [1] - specifically the CTS/RTS pinout seems to be reversed versus Yost.
• The Yost pinout given seems to be the DCE pinout, not the DTE pinout, per [2], but I don't know enough about Yost to know if that is relevant.

Hpa (talk) 19:29, 4 February 2012 (UTC)

I have added [3] as a reference to the pinout table. The table appears to match now. ~Kvng (talk) 20:38, 10 May 2020 (UTC)

Signal descriptions weak

The article does not adequately describe in detail what the various signals do and their levels. TxD, RTS, etc, what do they do? Logic levels? Wire voltage levels? For example, CTS, Clear To Send, means what when its high, what when its low? — Preceding unsigned comment added by 174.48.68.93 (talk) 16:34, 20 March 2016 (UTC)

Hmmm. I suspect that those should be in the RS-232 article, but maybe they aren't there. Gah4 (talk) 23:59, 18 October 2016 (UTC)

Is RS-232#Data_and_control_signals good enough? ~Kvng (talk) 17:37, 11 May 2020 (UTC)

Serial communications port?

Hard drives are, of course, not commonly interfaced through serial ports. Unfortunately, the are commonly interfaced through serial ports, just not the kind that are discussed here. Very generally, there are two ways to communicate data electronically, serial (with only one data line), and parallel (with more than one). Serial communications port might be a more specific name, though ss the ports discussed here are the more common use of the term, I don't think there is any need for change. A paragraph on other types of serial ports might be nice. Gah4 (talk) 23:23, 18 October 2016 (UTC)

Yes, different type of serial interface. See the second paragraph of the lead for a statement of scope for this topic. ~Kvng (talk) 17:39, 11 May 2020 (UTC)

Overview of serial port types

Does Wikipedia have an article that gives an overview/summary of the type, advantages, and limitations of the various serial port possibilities: RS-232, RS-422, RS-485 and any others I don't know about? With a title like "Serial Port" I would have expected that info here, but is mainly about RS-232 - which is great, but what about all the others? If such an article does already exist, please put a reference to it at the top. 210.185.102.135 (talk) 04:40, 26 March 2020 (UTC) And also references to the RS-422 and RS-485 articles, and to RS-232 and any others, if they exist. 210.185.102.135 (talk)

I agree, this would be the place for a comparison. A comparison would be a welcome addition. ~Kvng (talk) 17:18, 28 March 2020 (UTC)

No. I'm looking for a new car this year, I'm not going to look at an encyclopedia to find out what's the best one. This isn't Consumer Reports. --Wtshymanski (talk) 00:07, 29 March 2020 (UTC)

I think a better analogy in this case is looking for transportation. What's the difference between a bike and a dump truck? ~Kvng (talk) 17:42, 11 May 2020 (UTC)

Duplicated content

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

To not merge on the grounds that the topics are important and an a merge would put undue weight on a subtopic; readers are best served by having content separated. Klbrain (talk) 09:57, 15 January 2022 (UTC)

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As I see it, this article actually exclusively deals with PC serial port and as such duplicates information from the RS-232 article and also has a duplicate article COM_(hardware_interface). Some cleanup would be required; I't propose to either:

• Integrate the relevant content into the above mentioned two articles and rewrite this article to describe serial ports in general
• Rename this article to "PC Serial Port" and delete the COM article after integrating its content.

Any thoughts? --Arny (talk) 12:42, 30 November 2020 (UTC)

I agree that there's duplication, and that a strategy is needed to make these articles complimentary. However, I disagree that this article is or should be limited to the PC. I'm not exactly sure what you mean by that; lots of devices use serial ports, not just PCs. To this day, numerous industrial devices still use serial ports, especially for configuration or console purposes. For example, Cisco routers, PLCs, SCADA devices, microprocessor-based relays, etc.

The COM article seems redundant of this one. In my mind, "COM" is just a common name for serial ports on PCs, just like "LPT" was the DOS/Windows moniker for parallel ports. I propose the COM article be merged into this one. We don't delete established articles; rather we merge and redirect them.

RS-232 is the most common standard (incl. physical layer and the protocol) that is run over serial ports, but it is my no means the only. I would point out RS-422, RS-485, I²C, and UART as well. So definitely don't merge that one.

As well as the different standards (protocols), there are different connectors (pinouts). For external modems and some other peripherals, RS-232 was often run over DB-25, not DB-9. Cisco routers use RS-232 over RJ45. There are probably more permutations than I can list. The takeaway is that, while RS-232 over DB-9 is the most common serial port, it is not the only. – voidxor 16:58, 30 November 2020 (UTC)

Arny, I agree more with what I think voidxor is proposing. Serial port is a superset of COM (hardware interface). We can merge COM (hardware interface) into Serial port if we like. RS-232 is not the only type of Serial port so we can summarize RS-232 stuff here but push all the detail to RS-232. ~Kvng (talk) 18:12, 30 November 2020 (UTC)

You have brought several good points,voidxor & Kvng. I do find this mess a bit hard to solve though, as we have the mentioned three topics:

• Serial port: should define what that means in general and list the most significant types like RS-232, RS-422, RS-485, I²C, even USB and FireWire etc. That should be under this article's title and superfluous content should be moved elsewhere.
• PC serial port: as a variant of RS-232 specific to the PC and the "COM" article could be renamed thus (as "COM" is definitely not an official name for that!) However, perhaps the whole topic is not worth an article on its own but a section in the RS-232 article and a redirect to it?
• RS-232: fortunately the only proper article of the group. :) It doesn't need to be changed unless there are some more technical details in the above mentioned two articles which should be moved there as all general RS-232 technical details should be in that article.

--Arny (talk) 14:42, 1 December 2020 (UTC)

Arny, I am with you on your assessment of these articles. COM is the official operating system name for serial ports on an IBM PC compatible including modern Windows computers. I don't think it needs to be renamed but we can avoid that argument by agreeing that it does not need to exist. Of course, a COM port is both but I think COM should be merged to Serial port not RS-232. ~Kvng (talk) 14:51, 1 December 2020 (UTC)

I agree with Kvng. @Arny: I still don't understand where you're getting this "PC serial port" thing. A serial port is a serial port regardless of which device it's on, and that's the broader subject of this article. "COM" is synonymous with "serial port" on many PCs (i.e. how DOS and Windows refer to the devices, and thus how manufacturers tend to label the ports themselves). By contrast, on Linux, they're named /dev/ttyS1, /dev/ttyS2, and so on.

I still think COM (hardware interface) should be merged here. We can then establish in the lede section that "COM" is another name for serial ports. One section can briefly explain RS-232, as it is the most common serial port, then link to the main article. – voidxor 15:40, 1 December 2020 (UTC)

@Arny and Kvng: Are either of you feeling like you'd like to tackle this merger? I just noticed that the Serial port#Virtual serial port section seems more like a topic for COM (hardware interface) in the present state (as it's about the virtual device seen by the operating system, not the physical port), but there's no sense in me moving it if we're to proceed with a merger. – voidxor 20:14, 16 January 2021 (UTC)

Voidxor, I've updated the merge banners and added it to my todo list ~Kvng (talk) 15:57, 17 January 2021 (UTC)

@Kvng: Thank you for copy editing! Do you feel up to the task of merging COM (hardware interface) into this article, and perhaps pushing any extra detail out to RS-232? Thanks again for your hard work. – voidxor 22:21, 1 November 2021 (UTC)

I've returned to try and close this. Support for serial ports in specific systems is covered in Serial_port#Hardware_abstraction where there's a link to COM (hardware interface). There is not detailed information like this available for other systems so doing the merge would create WP:UNDUE coverage for this one system. The level of detail in COM (hardware interface) is not necessary in this article. For these reasons, I think it makes sense to leave these as separate articles. ~Kvng (talk) 23:10, 23 December 2021 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.