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As "RS-232" is a Protocol/Standard, "DB-9" is a type of Connector, Is RS-232 Cable a valid term? Or is there any proper name for that? "Serial Cable" maybe!

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I'd say "RS-232 cable" is a valid term. It isn't especially precise but I can imagine that such a cable might be designed differently than a cable designed for carrying other serial protocols/signals. I converted this from an answer to a comment because ... – RedGrittyBrick Dec 26 '13 at 12:25
This question appears to be off-topic because it is about opinions regarding the validity of popular terminology – RedGrittyBrick Dec 26 '13 at 12:26
RS-232 is not a protocol. It is an industry standard that defines connectors, signal levels, bit timing, symbol framing, signal functions, and maximum cable lengths. Any cable that complies with the RS-232 standard is an RS-232 cable. Any cable used for serial communications that does not comply with that standard is not an RS-232 cable...it's that simple. Would you call any cable that connects to a monitor a VGA cable? Of course not. – Joe Hass Dec 26 '13 at 14:33

Well both DE-9 and DB-25 connectors are used for RS-232, next you also have RS-232 over 8P8C connector (commonly used for network equipment console), you also have "null-modem" cables for connecting two devices of same type, there are various cable combinations depending on the gender of the connector and so on.

In my opinion, term "RS-232" cable by itself is pretty useless since it carries very little information. I do think that it could be useful in a field where sufficient amount of context is assumed when talking about cable type.

As for term "serial cable", well it's even worse than RS-232 cable. With RS-232, you can at least more or less safely assume voltage levels of the devices, with serial cable you can't. It could be a 3.3 V device or a 5 V device or a device using RS-232 levels. From cable's point of view, those are more or less same, but from device's point of view, the difference is important.

Furthermore, there are numerous other "serial cable" types which would have little in common with RS-232 cable. For example, there's the RS-485 which is also serial, there are various types of WAN connectors for network equipment that are sometimes called "serial cables" and have very little to do with RS-232.

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In addition to the assorted connectors that the cable could be using, internally it could be wired as a 2-wire, 3-wire, or 5-wire connection. – embedded.kyle Dec 26 '13 at 13:33
+1 If you're wiring a cabinet with known equipment, then instructions such as "disconnect the rs232 cable from the GPS module and restart the service" are meaningful, but for specifying the type of cable it could be any of the connectors you mention. – Pete Kirkham Dec 26 '13 at 13:35
@embedded.kyle I've had problems with a fax modem once because of that. It was configured for hardware flow control and I connected it using an RS-232 cable and it didn't work. Few continuity buzzes later, I discovered that the cable only had 3 pins connected. – AndrejaKo Dec 26 '13 at 13:39
So, It's not... Rather there isn't a specific term for that Cable... Shall I conclude this? – Swanand Dec 28 '13 at 15:27

Most of the communications cables I can think of are named after their particular protocol, e.g. HDMI, VGA, USB.

Perhaps the appropriate way to test validity of a name is to consider what it could be confused with. I can't think of anything that "RS-232 cable" could be confused with.

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I think today DB-9 is normally assumed and while I've thrown all mine out DB-25 RS-232 cables seem to still be available. Some of those used to only have the common pins connected not all 25. – PeterJ Dec 26 '13 at 13:26
Aaaah, I long for the days when you took whatever cable you had laying around, and stacked converters, gender changers, and null modems until something worked. – Scott Seidman Dec 26 '13 at 13:36
@PeterJ yea I call them DB-9 connectors but isn't the correct name actually DE-9? – geometrikal Dec 26 '13 at 13:42
@ScottSeidman I remember those times well :) – geometrikal Dec 26 '13 at 13:43
@geometrikal, never actually thought to check before but it looks like you're right and they're actually DE-9 because of the shell size. – PeterJ Dec 26 '13 at 23:42

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