Problem uploading to the arduino

It happened this morning and last night it worked well, so I cant think of something that has changed.

the pin13 smt led constantly blinks between 1 second to 1.5 second and when I try to upload a sketch to the arduino it says:

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

I have done anything; reinstalling the com serial port, changing it to 115200 baud rate (instead of 9600), disabling and enabling, pressing restart before uploading a sketch (although I never had to do it) and updating the serial port.

I would really appreciate it if someone could help.

Is the USB port set properly in Arduino IDE?

(* jcl *)

yes it is. i tried to plug the arduino into my other computer and blinking happened there too

Does the PC recognize the board when you plug in the USB cable? That is does the proper comm port number show up in the Arduino IDE? If not try another USB cable. I assume both PCs you tried have the proper USB FTDI driver and Arduino IDE installed.


yep the proper port number shows up when I conect the arduino (com 3, as always) and even the arduino environment refreshes and displays the COM3.

yep the proper port number shows up when I conect the arduino (com 3, as always) and even the arduino environment refreshes and displays the COM3.

Well you can run a test to see if the FTDI is functioning. Remove the AVR processor chip from it's socket (assuming you have a standard type Arduino board) and wire a jumper from pin 0 to pin 1. Now open the Arduino IDE and click on the Serial Monitor. As you type something in the serial monitor's output window and hit send the same characters should be 'echoed back' into the monitor's receive window. If that works OK then the problem is either with the auto-reset signal (you said your tried pushing reset, but the timing is tricky) to the AVR chip or the AVR chip itself (bootloader problem).

An easy way to check out the AVR chip is to buy a replacement that has the bootloader on it already:

Good luck;


i did see everything i typed typing back at me, so I guess I have to buy a new atmega. I guess ill buy the atmega without the bootlander because I can burn it later.

Thanks for all the help :)

Did you try re-burning the bootloader on the one you have?

I tried now, but after it burns the led blinking go again.

I have the same errors as the topic creator. Tried it on another computer (both Windows) and had the same result so the problem may be in the board.

in the board? i hope you say the microcontroller because the board is more expensive to replace

Hello. I´ve just bought my Arduino Duemilanove, made in china. I´m a newbe on this and i´ve the same problem. I´m using it with a notebook by usb port. Could be a problem of low amperage or voltage? I ´d try with an external dc power. Tomorrow I´ll tell you. Somebody tried with 4,5 volt ? Could it work?

seems unlikely because the arduino can be powered from a minimum voltage of about 2v, did you try the things i tried on my first post?

Thanks. Problem solved. I was choosing atmega 328 instead of 168. Now works fine and led switchs on, off, on, off,....It´s fascinating!!!!!!

guys... I still have the problem. I bought a new atmega168 and I used to program it by the USBtinyISP while it was on the arduino. It was all very well when I wanted to use the digitalWrite or analogWrite but when I wanted it to write something through the serial I couldnt do it from the usbtiny. So I burned the bootloader through the usbtiny and when It stopped burning the problem of the blinking came up again! what is the problem now?