Arduino Uno being disfunctional. avrdude and errormesseges included.

My two Arduino Uno's does not want to agree on my uploads.

It all started with a stepper motor. It ran fine at 9v, but according to the online community it would run even better with a 12V 0,5A external power source. I tried it, and it worked for a while. The motor kinda worked in motion, but it worked.

Now, after a couple of hours of playing around, it stopped accepting my uploads. It just said avrdude: stk500_recv(): programmer is not responding" After pushing the "restart" button many times, the error message was updated to

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

I've tried it with both a macbook pro and a windows pc. This is the avrdude from the windows pc.

C:\Users\nudelkopp\Desktop\arduino-0022\hardware/tools/avr/bin/avrdude -CC:\Users\nudelkopp\Desktop\arduino-0022\hardware/tools/avr/etc/avrdude.conf -v -v -v -v -patmega328p -cstk500v1 -P\\.\COM7 -b115200 -D -Uflash:w:C:\Users\NUDELK~1\AppData\Local\Temp\build3471245229859481650.tmp\Blink.cpp.hex:i 

avrdude: Version 5.4-arduino, compiled on Oct 11 2007 at 19:12:32
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/

         System wide configuration file is "C:\Users\nudelkopp\Desktop\arduino-0022\hardware/tools/avr/etc/avrdude.conf"

         Using Port            : \\.\COM7
         Using Programmer      : stk500v1
         Overriding Baud Rate  : 115200
avrdude: ser_open(): setting dtr
avrdude: Send: 0 [30]   [20] 
avrdude: Send: 0 [30]   [20] 
avrdude: Send: 0 [30]   [20] 
avrdude: Recv: 
avrdude: stk500_getsync(): not in sync: resp=0x00
avrdude: Send: Q [51]   [20] 
avrdude: Recv: 
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

avrdude done.  Thank you.

Are the two boards broken? I borrowed them from school, and i'm not really keen on buying them new ones :p

Does the leds turns on when you connect the USB cable on it? does you have power on the board? Try to measure the 5 V line on the board(Could be a power problem) Does the COM port appears on device manager on windows when connect it? Remove all the circuits and test it

Yes, the led turns on when it’s plugged in. I have no instruments for measuring the electricity though… I do think i’ve got power.

According to one of my groupmates, it could be my PC frying them from the usb, since our new one is also malfunctioning now. Not starting that windows pc up again.

On the mac it shows up, but won’t transfer the sketch.

I have been similar problems and asking for help on this topic
http://arduino.cc/forum/index.php/topic,75651.0.html
Lets try to merge these discussions.

Lets try to merge these discussions.

Let's not.

nudelkopp: I have no instruments for measuring the electricity though

An LED + resistor will indicate there is low voltage across any two points. Use a 500 ohm resistor for detecting up to 12 volts.

According to one of my groupmates, it could be my PC frying them from the usb, since our new one is also malfunctioning now.

Homer Simpson: Not a bear in sight. The Bear Patrol must be working like a charm.

Run this test... http://arduino.cc/forum/index.php/topic,73748.0.html