Arduino Uno port not detecting, L led is glowing continuously and Atmega328 is getting heated when connected via USB
checked replacing USB cable and done a visual inspection if any component is burned
Please provide the history of the board? Was it like this when you bought it? Did you use it and things went wrong; anything with 12V like motors/relays/solenoids?
That means more than likely that the TTL-to-USB (16U2, CH340, ...) converter has died.
That one is definitely damaged.
Conclusion: it's actually not worth fixing it unless you have the two components above in stock.
Sorry but it appears you fried it. The processor under normal operation should be barely warmer then ambient. More then likely you connected something to it that you should not have like to high of a voltage or an inductive load. Remember in the future "A Power Supply the Arduino is NOT!"
I have connected with cnc sheild on top and supplied a 24w power supply to shield, it was working when i bought
What is important is not the wattage capacity of a power supply but the voltage and the current.
It sounds like your CNC shield was either faulty, links not correctly set, or not compatible with your Uno, and that is what killed it.
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Well, shield was connected to 12v 2 amp supply as it would be required to power a 0.5w laser module
I think there's an internal short ckt in board,
Any idea why this problem occured.
I think we need to find out if it is an internal short first before we speculate about why.
An internal short in a PCB while not being unknown is very rare and it is something that is normally spotted at the PCB manufacturing stage. See if you can detect it with a resistance meter on the unpowered unconnected board.
It should be easy to spot because you will see it everywhere between power and ground. Knowing exactly at what point this happens is rather more difficult to find.
Board heats up as soon as connected to USB, no shield, no i/o pins is connected
That means the board itself is damaged. What we are trying to find out is how that happen, because if you buy a new board, and do the same thing to it, then the same thing will happen to it.
As you said that all you did was plug the shield in then that would suggest the shield is either damaged, incompatible, or the links have not been configured correctly.
Thanks for help,
Tried using another arduino board, the shield was damaged, which caused arduino uno board to fry,
As soon as connecting another arduino board to cnc the laptop screen went blank.
Try another USB cable
Tried before, same thing repeated
If the board heats up when plugged in, then the problem is not one of using a faulty, or charging only cable.
So that is saying there is a short circuit somewhere and the USB power of your laptop is shutting down.
Can you supply a link to where you bought the CNC controller board.
from amazon, can't find seller now.
So can you at least send a photograph of the shield?
I had some issues with power input points on shield, its was loose, would swivel when screws were lightly tightened
You do know that just using that board is not sufficient?
You need stepping motor drivers plugged into the three yellow and one red header pins.
Maybe this is one of the Chinese Clones the web site talks about?
Pity you could have sent it back to your suppler as faulty.
I have connected cnc shield and laser module via buck convertor to common power supply (12v 2amp)
I have used new arduino uno & cnc shield paried with old stepper drivers, once again same issue of over heating of arduino board repeated
After testing i have found that one of stepper driver's heat sink is getting heated as soon as connected ( even when when stepper motor pins for that section is removed)
So i removed all connection of shield and tested current consumed by cnc shield connected one stepper motor driver at a time, and the one that was getting hot would show consumption of 10mA and when connecting only seconds driver to shield it consumes no power
Conclusion found - if nothing is connected to shield then power consumed by shield should be zero, but with one of driver it shows 12v 10 mA consumed, does it means that there is short ckt in one of stepper driver ?
