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I just stumbled over an old construction article where an option to use a 20mA current loop instead of RS232 is included. When was the last time you saw any device use that or at least have that option? The problem is more relevant today than ever before, but I think that current loops are now a thing that you can find in a museum, or am I wrong there?
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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Never used a current loop but multileveled PWMs are quite common.
GCS/GE d--(d) s-/+ a C+++ U+++ P-- L+@ E-- W+++ N+ o+ K- w+++ O? M-- V? PS+ PE Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
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Before about 35 years I was in contact with 20mA current loop.
We used it because it was easy making galvanic isolation.
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0x01AA wrote: Before about 35 years I was
...not existing on this planet in this form.
"It is easy to decipher extraterrestrial signals after deciphering Javascript and VB6 themselves.", ISanti[ ^]
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CodeWraith wrote: I think that current loops are now a thing that you can find in a museum, or am I wrong there?
Lots of hardware in the maritime industry still using current loops today. Kongsberg, Baker Hughes, Hatteland, Rolls-Royce... many others, too many to name.
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Ah, ok. Reliability instead of shiny and new. Makes sense.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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CodeWraith wrote: Reliability
Yep, I just looked through the Raytheon and L3 products and see they are still using them too. I use to work with alot of maritime hardware. We were converting currrent loop to RS232 to interface with our PLC back then.
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CodeWraith wrote: I just stumbled over an old construction article where an option to use a 20mA current loop instead of RS232 is included.
I actually run into things that use serial in the IoT realm and while i'm usually using a USB to serial bridge like a CP2102 or a CH340, some little devices break out to RS232.
The thing is, I have no idea what a 20mA current loop is or why it could replace the functionality of a serial interface?
And it's something I feel like maybe I should understand. What sorcery is this?
To err is human. Fortune favors the monsters.
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Old and ancient magic, used for teletypes and later for computer terminals. As an old standard, it was slower than RS232, but is also known for its high noise immunity.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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CodeWraith wrote: also known for its high noise immunity
Cable length[^] is a limiting factor for RS232. Also the reason why some industries are still using current loops. 
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… or RS485
I’d say current loop is confined these days mostly to analog 4-20 mA sensors
Mircea
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Mircea Neacsu wrote: current loop is confined these days mostly to analog 4-20 mA sensors
Yes, I would say it's the industry standard in some areas. There are many thousands of industrial sensors using current loops even today.
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Cobol is still used, my dear.
"In testa che avete, Signor di Ceprano?"
-- Rigoletto
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Last I heard of it was the Lenz RS-Bus used in model trains - no idea if it is still used, I just read about it back 5-10 years ago.
I have been tempted to hook up a remote sensor with current source to run two wires only (as an alternative to 1-wire but less prone to noise or capacitive problems on longer runs). Never got off the ground though, and I do not remember what it was I wanted to sense, so it was probably not important. 
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Hardly qualifies as a loop but I have a current sensing switch that turns on a device when a pump starts up. Monitors the current on the AC line to the pump.
>64
Some days the dragon wins. Suck it up.
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Message Closed
modified 15-May-23 19:06pm.
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Well, I basically agree with you.
"In testa che avete, Signor di Ceprano?"
-- Rigoletto
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Totally agree. Yes, I understand that, (particularly for long-standing loungers), it gets to be pretty tiresome when posts are not in the spirit of The Lounge - or even breaks "The Rules". But, hey: who reads the rules?
Back in the day  , in the UK, "The Lounge" was the quiet(ish) room in a pub, where strangers were met with stares and silence. It wasn't very welcoming. We should try not to fall into that trap. Let's try to be more welcoming and recruit our successors. One day we're all going to be dead. Who's going to do the CCC then? 
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5teveH wrote: We should try not to fall into that trap.
Staring and silence are my specialties.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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Same AI devices that take over development.
They can do each others homework. 
>64
Some days the dragon wins. Suck it up.
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Sounds like a lot of saloon bars I've come across, too. Often the saloon (or even "public") was more cliquey than the lounge.
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Member 14968771 wrote: why business is loosing customers
losing, not loosing.
Member 14968771 wrote: 2. replies concentrated on correcting the poster English
Oops! 
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>64
Some days the dragon wins. Suck it up.
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Actually, loosing (as in releasing) sort of works in this context.
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