Arduino upload problem: avrdude: stk500_getsync(): not in sync: resp=0x00

There are a number of good posts out there discussing problems with uploading sketches to an arduino, but my problem was really basic:

I had some wiring connected to digital ports 0 and 1 (TX and RX) and that was causing communication errors. I unplugged the wires to those ports and the upload then worked just fine.

Here is the post that helped me:

  • Big Hurry

    After encountering the averdude error while uploading programs to Arduino UNO I discovered the COM port was incorrect in the programming environment. Go to Tools, Ports and select the port the programmer is connected to.

  • Thomas Beutel

    Thanks for the additional info! – Thomas

  • Raúl Tauber

    Dear Sirs:

    I´ve Arduino Board with processor Atmel 328P connected to PC (COM 2) through
    USB 2.0 to UART TTL 6PIN Module Serial Converter CP2102.
    The data acquisition from board to PC is correct, using Tool>Monitor,
    but the problem is presented when I want to do an Uploading from
    PC to Arduino Board, using sketch or examples, with the following message:
    - avrdude: stk500_getsync(): not in sync: resp = 0x00.
    - avrdude: stk500_disable(): protocol error, expected = 0x14, resp = 0x51.
    I hope some help from You.
    Thanks, Raúl

  • AndresSanMar

    You're awesome. I'm new to Arduino programming and for a moment there I thought I just blew up my recently acquired Arduino Uno. Read lots of forums and my problem was this simple, thanks a lot!

  • Ben Benavides

    I had the same problem with Arduino MEGA 2560 R3

    avrdude: stk500_getsync(): not in sync: resp=0x00
    avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

    I fixed it with this info

    Drivers section