Unable to upload firmware to a new motherboard I bricked my Tevo Tarantula's controller board, and I've decided to just replace it rather than unbrick it because they are relatively cheap. I recently bought a new MKS GEN L v1.0 board, but I've been unable to flash new firmware onto it. Every time I go to upload the firmware, I get an error just as it begins to upload, saying:
&quot;failed to send command to serial port does not exist or is not connected&quot;

avrdude: stk500v2_ReceiveMessage(): timeout

avrdude: ser_send(): write error: sorry no info avail

avrdude: stk500_send(): failed to send command to serial port

avrdude: ser_recv(): read error: The handle is invalid.

avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer

Any ideas of what the issue could be? I've tried both the USB ports on my computer and using a USB 2.0 hub (I believe my computer ports are both USB 3.0). I've also made sure that I had the correct port selected in Marlin (1.1.8.13).
I also think that its worth mentioning that my bricked board and new board seem to appear differently in the device manager
Bricked:

While my new board appears as this:

The new board also seems to &quot;cut-out&quot; when I first connect it to my computer as well. In the device manager, my computer will indicate that an unknown device is connected, then it will quickly disconnect and disappear, only to reconnect and reappear as pictured above.
Do you guys think there is a hardware issue with the motherboard? Thanks for your help, this is giving me quite the headache!
Your motherboard is not an MKS GEN L v1.0, it's a MKS SGEN L - unfortunately, a very very naming scheme.
Your board is actually a 32-bit board, and must therefore be flashed with Marlin 2.0, built for the 32-bit board.
The firmware is then updated by placing it on the SD card and restarting the board, as explained in the documentation for Marlin here