Loop Back Test - Sticky?

Connect a jumper from the TX pin (Digital Pin 1) to the RX pin (Digital Pin 0)

Strictly speaking, they aren't pins. If you are going to worry about people not hearing sounds because the volume is down, you might point out that they are sockets. It's the male/female thing. The boards only have a handful of pins, the rest are sockets.


And I can't resist this:

Graynomad:
I hope I'm not splitting hairs but this is for beginners.

Windows produces a device insertion tone

Not if sound is disabled.

Warning: if you are deaf you won't hear it.

You certainly have a valid point. Unfortunately, the Arduino folks call them "pins" A. I prefer to use the same term used in the rest of the Arduino documentation to avoid confusion B.

A Which has been a source of confusion even for advanced users (Did you mean "physical pin" or "Arduino pin"?).

B Oh, the irony!


Warning: if you are deaf you won't hear it.

XD

As part of a previous job, I occasionally had to install a complete computer system (PC + custom software). I arrived at one of the sites and found the two operators. One of the operators ("Buddy") was bragging to the other ("Juan") about the new tires on his truck. He claimed to have reached more than 80 miles per hour and successfully navigated an especially sharp corner. I had a suspicion Buddy would need a bit more training than usual.

I carried in the various computer parts and connected them. When I left the office to get the software and some notes, the computer was fully assembled so I started it booting. I returned to the office to find Buddy waving the mouse in front of the monitor with a very confused look on his face. Juan watched for a moment and then told him, "Buddy, you have to drag it across the table." I very nearly burst out laughing; I had to actually cover my mouth. I turned around, walked out the door, sat down in my vehicle, and laughed my gut sore.

Despite his naiveté, Buddy was up to the task. He quickly learned, not only to use a mouse, but to use the software.

The moral of the story? While instructions like "Warning: mouse only functions correctly when used on a flat horizontal surface" are sometimes necessary, "Warning: if you are deaf you won't hear it" is probably over the top.

Now a sticky...
http://arduino.cc/forum/index.php/topic,73748.0.html

Please continue posting suggestions here.

Is it safe to assume that newcomers will know that they should look for how to perform a 'loop back test' when uploading doesn't work?

The title of the sticky post doesn't say anything about failing uploads.

Actually, after the revisions suggested above, this is really good. The only thing that struck me was that when I first saw it I asked myself, "What do I want to do a loopback test for?" Perhaps, something about why one would/should do a loopback test?

I tried the procedure and had no difficulty following it.

The slight change I wanted to suggest was that some of the text in step 8 should be removed and instead there should be a short introduction saying why you would do the test and what it would achieve. I reached this conclusion before reading this thread where one of the comments is;

The only thing that struck me was that when I first saw it I asked myself, "What do I want to do a loopback test for?"

Suggested text at the start (removing equivalent text in point 8 );

The loopback test will prove that your host computer hardware driver, USB cable, and USB to serial converter are all working.
Try the loopback test after you first install the system or if you cannot upload sketches.

madworm:
Is it safe to assume that newcomers will know that they should look for how to perform a 'loop back test' when uploading doesn't work?

No.

The title of the sticky post doesn't say anything about failing uploads.

What should the title be?

What introduction (cover) should be added? Perform a loop-back test when...

draythomp:
Actually, after the revisions suggested above, this is really good.

Excellent!

The only thing that struck me was that when I first saw it I asked myself, "What do I want to do a loopback test for?" Perhaps, something about why one would/should do a loopback test?

I agree. One case is: uploading was working, upload is not now working, damaged processor is suspected. When else would / should a loop-back test be performed?

radman:
I tried the procedure and had no difficulty following it.

Excellent! Thank you.

The slight change I wanted to suggest was that some of the text in step 8 should be removed

Nope. Not going to happen. My Tech-Com II professor stated repeatedly: You tell it to them three times. You tell them what you are going to tell them in the introduction. Then you tell them in the body. Then you tell them what you told them in the conclusion. After working in technical support for a few years, I strongly agree. Some people get it the first time they read something. Some people barely get it the third time they read something. Troubleshooting instructions need to be written for the latter group; lots of repetition.

and instead there should be a short introduction saying why you would do the test and what it would achieve

I agree. It needs an introduction / cover.

Suggested text at the start (removing equivalent text in point 8 );

The loopback test will prove that your host computer hardware driver, USB cable, and USB to serial converter are all working.
Try the loopback test after you first install the system or if you cannot upload sketches.

Is it necessary to perform a loop-back test after first installing the system?

Is it necessary to perform a loop-back test after first installing the system?

No. The loop-back procedure is a troubleshooting aid/procedure to help one determine if serial communication between the PC and Arduino board is working or not working in a typical arduino installation. It does no harm to run it on a working system, and it would probably be best to learn to run it on a working system before having a problem to prevent false positive (or is it false negative?) testing results.

Lefty

Is there really just one use-case? "uploading was working, upload is not now working, damaged processor is suspected"?

How's this for the introduction...

The loop-back test is a troubleshooting procedure to determine if serial communication between the PC and Arduino board is working in a typical Arduino installation. The test proves that the host computer, hardware driver, USB cable, and USB to serial converter are all working.

How's this for the introduction...

Needs a comma between "host computer" and "hardware driver". It is testing all 4 items.

Thanks! Done.

So treat everybody like dummies because there might be one or two in a dozen !
How did the dummies get into your professors class?
When I went to uni it was stay up or get out

Not everyone that needs repetition is a dummy. Some folks read this board in their second or third language. Some folks use google translate to read it. Some folks are beginners at everything electronic. Like it or not, repetition works. It gives the person a second chance to hear it, it gives the translator a new version to try and screw up differently and it helps to reinforce information.

Besides, being snide doesn't help.

The current state of the introduction...

We have one use-case.

Should the sticky include references to example / related topics? Some examples...

http://arduino.cc/forum/index.php/topic,75651.0.html

Any more comments before I change the sticky?

I like the introduction. Short, and to the point.

I have mixed feelings about the examples, they might confuse more than help. I'll bow to other's opinions on that.

Good job.

Introduction added.

Any more comments about examples / related topics?

Any other use-cases?

Should try without the jumper as the Terminal program could have a ECHO turn on
Patgadget

There have been issues with 'clone' boards lately.

They didn't come with either the ATmega8u2 or the FT232R, but with some IC by 'Prolific'. Suffice to say people were still trying to install the FTDI drivers or the .inf file, depending on what their clone pretended to be.

Maybe there could be a note/hint to check the vendor/product IDs if the 'Arduino driver' refuses to install.

Addendum:

Of course we could say "why should we care?", but in the end people with these modified clone boards end up here and we spend our time that would be better spent elsewhere.