I have the right Board and only COM port selected, I can receive Serial Data (nothing, but it is coming through) and still I get the AVR error, ios there something I am doing wrong in the upload, I only click the upload button on the PC, nothing else.
Take a wire and connect RESET to GND to disable the microcontroller.
Then take another wire and short pin-0 and pin-1.
Use the serial monitor and input some text. If you press SEND, it should be echoed back.
If that works, it may be a bootloader problem or a dead chip.
You can try changing the upload speed of the IDE for your board. It's either 19200 or 57600.
Changes need to be made in boards.txt + restart of the software.
I'm having the exact same problem except with a new arduino mega. The loopback test works fine and ive tried changing the upload speed to both 19200 and 57600
I am having the same problem as chankster. I tried all of the things in the troubleshooting list on the arduion website, and none of them worked. I tried linux, windows xp (in virtualbox with usb port forwarded), and windows vista x64, and all gave the same error. (avrdude: stk500_getsync(): not in sync: resp=0x00, avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51). This is a brand new arduino mega. Just came in today from liquidware. The loopback works fine with the serial monitor. I have the correct port and board selected. When I try to send the blink program, the receive led blinks three times, but the transmit light never comes on. Any ideas?
Here's the response I got from the guys at liquidware
Hi Travis,
At first I didn't believe it, because I have my Mega here and I just programmed just fine!
So I told Mike about this and he suggested grabbing a Mega from the latest batch. He tried to program it, but got the same issue you described -it can't program!
There is definitively something different about the Megas produced 1 months ago versus the more recent batches.
I've copied Mike here because he is in regular touch with the Arduino guys in Italy. He's getting in touch them now and as soon as I hear more, I'll keep you posted.
hey guys, i just saw this post come up about the mega... i don't really know what it might be, but the one i have at home works perfectly? i have a vista laptop that pretty much never worked (for some reason the driver crashes my computer every once in a while when it downloads, but that's with the diecimila and duemilanove too), so i always do programming on my xp desktop.
sadly i'm still at work but i'm going to run home as soon as i can to see if i can help. in the meantime i just emailed chris too i think he's home, and maybe he can see what's up?
Hi... i just tested 6 of the new Megas in my book case and none of them will program with Arduino 15 or 16.
i'm going to test the rest and see if i can figure out why these Arduinos aren't working...
update...
I just checked all of the Arduino Megas i have in my apartment...
The 3 that i first bought (in April) from the arduino team in italy worked fine.
The new 58 Arduino Megas (i bought in May) don't work at all... not a single will program!
I tested the ftdi usb circuitry and that checks out fine...
I just took out my AVR ISPMKII and i will test the fuse bits on the processor to see if they are different from my working Megas...