Hi,
I have been trying to use an Arduino UNO to control a project of mine. I can get it to work for a few days, but after that usb fails, so I can no longer upload projects to the Arduino. The arduino doesn't show up device manager, or in the arduino programmer. The microcontroller on the arduino is still running my code and doing everything it should, but I can't access the arduino to upload new code. I've tried two arduinos and both have suffered the same fate :'(.
Does anyone have any suggestions for what could be causing this ?
I'm using Windows 7 64 bit, the latest arduino software, and Arduino UNO.
Hi,
when trying to upload to the board I don't have anything connected, but normally I have the circuit below to control a motor, (three relays to turn on and change direction).
Try connecting it to a different computer and see if it shows up in device manager on that computer.
If it doesn't show up at all in device manager, and if it has an ATmega16U2 for the USB-to-serial chip you could try re-flashing the firmware to the ATmega16U2 using the ICSP header right behind the USB socket.
You should not use USB cable to debug Serial monitor with arduino connected. Always use external power supply when running motor & arduino board
when you trying to upload code what error you got . send us error of the message with quotes
Usually in this case either usb keep detect & greyout while uploading code OR your USB to TTL IC might got damage. check when you connected USB device the IC gets heats or work normally.
" avrdude: stk500v2_getsync(): timeout communicating with programmer "
Which is not surprising since the arduino isn't showing up anywhere. When it was working the arduino showed up in sketch program as "Arduino UNO" but now nothing.
I tried following the instructions for reflashing the USB chip, but it will not show up as "DFU" with it put into DFU with the jumper wire.
I've tried three PC's and three different cables, all the same result.
So it seems the chip that communicates over USB is getting blown, but how and why ? I'm wondering if it's the back-emf from the motors that are damaging it ? I have protection diodes (1N4007) on all of the coils / motors, but maybe they're not fast enough and it's somehow damaging this IC. Is the USB chip particularly sensitive to the kind of voltage spikes you might get from motors and relays ?
