Computer not recognizing Elegoo Mega 2560 R3

I also am having issues connecting to my computer. I have bought a Elegoo MEGA 2560 R3 off of Amazon and my computer will not detect it. I have tried many different cables, usb ports, computers every driver I could find. Nothing works :frowning: . I was able to upload maybe 2 sketches then it never worked again.

Hi there!

Can you look near the USB port for a small black chip? I attached a picture of what it might look like. Let me know which one you see.

In addition, can you go to device manager and see if there are any “Unknown Devices” listed?

USB2SerialConvs.png

Hi!
I have the same model of Arduino and the same problem (mine uses MEGA16U2). I will keep trying to solve it for a while. If I do, I will post it here.

I see that you have been able to upload and (I'm assuming) run sketches correctly. What were these sketches designed to do? Were they powering any device that requires a lot of current?

I had a Due fail because I was trying to connect it to my computer while I had a projecter plugged in as well, and I think the power that the computer was trying to pump out was too much for the little chip, which is used as a USB to Serial converter so the computer can talk to the Arduino.

Same issue here:
My Mega 2560 R3 has the ATmega16u2

I had it working for a good part of the afternoon yesterday and then I began to receive his error message:

Arduino: 1.8.5 (Mac OS X), Board: "Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)"

Sketch uses 1462 bytes (0%) of program storage space. Maximum is 253952 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 8183 bytes for local variables. Maximum is 8192 bytes.
avrdude: ser_open(): can't open device "/dev/cu.usbmodem3A21": No such file or directory
ioctl("TIOCMGET"): Inappropriate ioctl for device
ioctl("TIOCMGET"): Inappropriate ioctl for device
avrdude: ser_send(): write error: Bad file descriptor
avrdude: stk500_send(): failed to send command to serial port
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: ser_send(): write error: Bad file descriptor
avrdude: stk500_send(): failed to send command to serial port
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: ser_send(): write error: Bad file descriptor
avrdude: stk500_send(): failed to send command to serial port
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: ser_send(): write error: Bad file descriptor
avrdude: stk500_send(): failed to send command to serial port
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: ser_send(): write error: Bad file descriptor
avrdude: stk500_send(): failed to send command to serial port
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: ser_send(): write error: Bad file descriptor
avrdude: stk500_send(): failed to send command to serial port
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer
the selected serial port avrdude: stk500v2_getsync(): timeout communicating with programmer
does not exist or your board is not connected

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

I told you a few days ago that I had the same problem. Well, it finally worked!! In my case, the problem was the wire I was using. I tried another one (the one I had for the printer) and it worked!! I am such a happy person right now!

adriansg95:
I told you a few days ago that I had the same problem. Well, it finally worked!! In my case, the problem was the wire I was using. I tried another one (the one I had for the printer) and it worked!! I am such a happy person right now!

Yeah, the cable needs to be USB data cable; one where all 4 pins on each end are connected.

We say that every time, but many people don't listen.

.

Updating the Atmega8U2 and 16U2 on an Uno or Mega2560 using DFU

I have been using different cables different usb ports... nothing is working. I have the mega16U2

I know this is an old topic post but I had the same issue and found a fix.
I ended up switching the board type int he tools drop down menu. the software defaults to the Arduino Uno. Changing it to the 2560 fixed my problem. Hope this helps someone.