Hi, I am very new. everything was working fine on my project. Then it wasn't. I tried to hook up the board to the computer to run the serial monitor so that I could make sure it was receiving the inputs and triggering the output but get "board at com 4 is not available" when I click on serial monitor. I try to open the "ports" drop down in the "tools" drop down on Arduino software, and it is not clickable? Any help is appreciated... Thanks
Sorry more info:
Windows 10
running an uno and it is selected as the board
tinvestor:
everything was working fine on my project.
Do you mean that the board's port was previously recognized by your computer?
If so, try restarting your computer. That has solved this problem for me in the past.
No, I mean that I had it out in the real world performing for weeks perfectly. Then when it failed I couldn't reestablish connection to diagnose the issue.
UPDATE:
connected a virgin uno to the computer and it installed on port 3 but again cant connect to it... Cant click on port in tools menu either to change it.
If port menu is greyed out, that means that the operating system is telling it there aren't any serial ports, so there's noting it could display in that menu - ie, you either have driver problems, or the board connected is damaged.
For your new uno - is it a clone from ebay? Those use a different serial chip (usually a CH340G or CP2102). Check the markings on the black chip near the USB connector. If it's an Atmel 16u2, that uses the official drivers. If it says one of those other part numbers, google that part number, your operating system, and the word drivers (note - there will also be a second number on the chip; that's a date code, not the part number)
For your old uno - does it work on other computers? Is it an official Uno? Were you doing anything that might be considered abusing the power rails? The 16u2 on the official board is fairly susceptible to damage, particularly from abusing the power rail.
A few other "silly" causes:
There is a scourge of bad USB cables making the rounds. Yes, you read that right. Try it with a different cable.
Try it in a different USB port.
Try power cycling the computer (in case you shorted the Arduino and the computer decided "yikes there's a short on that port, better shut it off" - some will do this and not reenable it until a full restart).
Thanks I posted a VERY long response and my computer decided to have network issues so it was lost
I got it running but have no idea how? I didnt do anything that I hadnt done many times before. I used a new computer. I only use my trusty printer cable for projects as I read about the bad cords somewhere. It is identified as CH340 (no G)
I finally got it to let me see com ports and played with them til they matched in device manager and in"tools" on arduino software. BUT it then started giving me avrdude error message for COM1 WHen everything matched to COM3 so I dont get that??? I uninstalled all of the instances of CH340 on the com ports several times and re connected the board several times and it just finally worked
Problem is I dont want to spend 8 hours connecting a new board every time I need to. Any Idea what idiot user error I am commiting?
Thanks for all the help.
Sincerely,
Should have stayed a sheet metal worker