Hi! My Uno cannot be read by my laptop anymore. It does not appear on Arduino IDE or PlatformIO. Tried both Windows 10 and Linux (Zorin). On Windows' Device Manager, it does not appear at all. "Ports (COM & LPT)" category only includes items for Bluetooth, and does is not even present when Bluetooth is off.
Replaced cables, still nothing. Its powering on though (Imgur vid, captured last night). Laptop USB port seems fine though since I can use it for other things, e.g. ext HDD, flash drives
Also the built-in LED seems to behave weirdly (Imgur vid, captured this morning). Its fading in and out when placed on a flat surface, but stays off when lifted. Also adding a jumper wire to pin 13 lights it up fully, even if the other side is not grounded. I suspect it might be shorted somehow, maybe the other pins too so the computer cannot read it, but I'm not entirely sure. Not really confident with de/soldering pins either.
Last time I used it was a few weeks ago. Its been sitting inside a box since then. Wasn't wet or anything. Maybe got a bit too cold since its raining often here lately.
Any suggestions for diagnosing the issue? Can I safely test the pins with a multimeter? Thank you very much in advance for your inputs.
The L led behaviour is normal for original Unos and a number of clones. There is an opamp that drives the led; the input picks up noise from the environment if it is not actively driven by the main processor.
Hello, using tail -f /var/log/syslog shows nothing. Tried starting the command before plugging in the Uno, and replugging it back in while the command is running. No update (aside from other system processes). Here's the actual output:
myname@computername:~$ tail -f /var/log/syslog
May 29 20:01:40 computername systemd[2306]: tracker-store.service: Succeeded.
May 29 20:02:13 computername PackageKit: daemon quit
May 29 20:02:13 computername systemd[1]: packagekit.service: Succeeded.
May 29 20:04:37 computername anacron[905]: Job `cron.weekly' started
May 29 20:04:37 computername anacron[9184]: Updated timestamp for job `cron.weekly' to 2022-05-29
May 29 20:04:37 computername anacron[905]: Job `cron.weekly' terminated
May 29 20:04:37 computername anacron[905]: Normal exit (2 jobs run)
May 29 20:04:37 computername systemd[1]: anacron.service: Killing process 9187 (update-notifier) with signal SIGKILL.
May 29 20:04:37 computername systemd[1]: anacron.service: Killing process 9188 (shuf) with signal SIGKILL.
May 29 20:04:37 computername systemd[1]: anacron.service: Succeeded.
You're not offensive. Note that I said "original Unos and a number of clones".
My SparkFun Redboard does not have that opamp and does not exhibit the behaviour that you described, my Unos however do.
Take a 10k resistor and connect pin 13 with it to GND or Vcc and check the behaviour of the led in both cases. GND should dim the led, Vcc should switch it on.
What wad the last project that you were working on before or during which it failed. Anything with motors, relays, voltages different from 5V?
What wad the last project that you were working on before or during which it failed. Anything with motors, relays, voltages different from 5V?
I couldn't remember exactly but its probably running a very tiny stepper motor directly like in this vid. I know that sounds foolish but the motor is really tiny so I don't think it drew that much current.
Deleted my previous message bc I forgot to hit the Reply button...
The project I mentioned is actually the latest one in my folder. However I couldn't remember if I uploaded an older sketch on the board for sanity check. I recently had some trouble making very basic code work on TinkerCAD