Hi, i bought an arduino mega2560 with the CH340 chip for cheap, and i was able to upload a code to it for 2 or 3 times and after this it simply doesn't show on the arduino IDE and doesn't even shows on the device manager, i already tested with other cables and another computer, any suggestions? Thanks!
Does it show up in Windows Device Manager?
ieee488:
Does it show up in Windows Device Manager?
No, this is the problem, because i already have the drivers for it
Dead ch340 chip? Does the Loopback Test work? (topic at the top of this forum)
CrossRoads:
Dead ch340 chip? Does the Loopback Test work? (topic at the top of this forum)
I tried it but Windows doesn't recognize it so i don't have how to send things to the arduino, I think the chip is dead 
You might have corrupted the bootloader , there are guides to re enstalling that .
Also you can still program via the fdti (?) , 6 pin connector at the other end of the board , or reload bootloader here.
I have a couple of boards that I can still use like this even tho the USB no longer works
It's not a bootloader issue if it doesn't show up in device manager.
You realize that it will show up as a serial adapter, not a mega2560 in device manager, right?
Could you be using a bad USB cable? (there's been a plague of these lately)
Did you have anything connected to it? If so, remove the external devices in case they're loading the power supply.
Do try other usb ports. Have you rebooted the computer (or tried a different machine) since it happened? Some systems will turn the USB port off until reboot if an overcurrent condition is detected.
Also, Windows will turn off a USB port as a power saving feature. You must change the setting to prevent that.