I have been trying to figure this one out also. I have looked at a long list of other peoples issues with this common error message. "avrdude: stk500_getsync(): not in sync: resp=0x00". No one seems to have figured it out or I haven't looked in the correct place for the answer.
I am building a project on a PCB that uses an ATMege368P-UA, the 32 pin TQFP package. I have written software on a UNO and it works well on the UNO. I am now trying to get any thing, Including Blink, to work on my new pcb that I designed to work just like the uno minus the USB chip. I will be loading the data via a serial RS232 port with a MAX232 level converter chip. I used the link, http://arduino.cc/en/Tutorial/ArduinoToBreadboard to load the boot loader. It seems to be working. When I upload it resets and the light blinks three times, then nothing. I want to be able to do software updates via the boot loader from a PC serialRS232 port, less expensive. I have checked the hardware over and again and it is as checked as good as I can do and seems to be correct.
When I try IDE ver 1, to up load the simplest program or any for that matter it comes back with, avrdude: stk500_getsync(): not in sync: resp=0x00. I've look at the hardware config files, I've look at the preference files for any thing that might give me a clue. I have also tried this with version 22 and it includes another error message,
avrdude: stk500_disable(): protocol error, expected=0x14, resp=0x51
I know this question has been ask before but I can't find any suggestion or remedies. Can anyone point me in the right direction? Would it be an advantage to have a real in circuit serial programmer rather that using the UNO to burn the boot loader?
Thanks, You pointer me in the right direction. Nothing was wrong with my circuit except ... we , I should say I didn't spend much time regarding the serial level conversion analysis. Seems like a no brainer right!. Well we are designing this to work in an RF environment and we put bypass caps on the serial lines for rf proofing. Well the impedance of .1 uf caps at 115khz is only a few ohms. Well the caps were antenuating the serial signals to the point where there weren't any at high baud rates. Removed the caps and wala. It works and blinky is blinking away. Sometimes it's the simplest things that make you want to pull your hair out.
Stank, your project is interesting.
I know that a decoupling capacitor seems to short the circuit while working at high frequency, like 100K hz as you mentioned.
You mean the signal is running at 100K hz or the system is working in a environment with strong RF influence. Just curious.
Thanks.
I am cloning a ArduinoUnoR3 right now, and I am still struggling with bootloader issues, I can't get rid of that error :
avrdude: stk500_getsync(): not in sync: resp=0x00
I am building a device that works in the High Frequency bands, 2-30 MHZ so it is important to keep stray rf fields out of the circuitry. I guess I was a Little over zealous with my bypassing caps. In the Uno serial upload environment the baud rate is 115 kilobits per second, 115khz, that actually requires a transient response much higher than that to make sure your square waves stay square. As far as the error message goes, I guess it wasn't seeing any response from the Uno because the Uno was not seeing valid data. I think some of my bits were disappearing through the bypass caps.
This my first try at loading the boot loader and it worked fine using an Uno for the icsp. Once I switched to the RS232 driver I had the problem. Anyway, Now I have a problem with my LCD device. I have use a Lumex display up til now but I needed a different form factor so I changed it and now it doesn't work right. It seems the initialization isn't working correct, everything looks like chinese. You fix one problem then you have another.
One other thing, make sure you are operating your serial port at the correct baud rate.