I have a Arduino Uno board that seems like it got stuck ... it was working fine and all of a sudden I did not see the device anymore on the ports.
I have the arduino driving a ardumoto shield connected to a small 12V dc motor. At the moment that the board disappeared from my system, I was trying to change some wiring on the external powering of the ardumoto with a 12V source (tested with voltmeter also for polarity). By the way, it was not the first time that I was playing around with those connections as the motor was always working perfectly except for the fact that whenever I would try the external power it would not understand the 'reverse' command.
I have tried to read more or less all the messages related to disappearing ports (I am on mac OSX) to no avail.
To be sure, the problem is not with my PC or drivers, because I actually went to buy a new board, which works perfectly.
The 'faulty' board has the ON led light on, and the led on 13 blinking but, again, I do not see the device
Any suggestion on how I could troubleshoot this problem? Even if the board is gone, I would like to know what is wrong with it, so that I learn for next time.
I had an issue last night where I couldn't upload sketches. Removing the wire from Pin 0 done the job and then I could put it back in after upload. Worth a shot.
the problem is not with my PC or drivers, because I actually went to buy a new board, which works perfectly.
You will need a friend who has hardware knowledge to research... It sounds like a component got "fried" since the new board works correctly. If just the ATmega328, you are only a few dollars from a fix. Anything else will require a skilled individual. The blinking LED does not prove the two microcontrollers are working on all pins.
Yes, I did try the loop-back instructions. The led in 13 keeps on, but I stop at
Connect the terminal application to the serial port for your board.
because the computer does not see the board.
It will take me a qhile before I can sketch the full circuit . But I will have to do that anyways at some point: when I have it, I will post it ... the only thing that I know is that the circuit is working with the new board.
@RyanfaeScotland: What do you mean by "Removing the wire from Pin 0" ?
I am now using 8x1.5V AA batteries to supply the needed power to the ardumoto board.
At the time the board failed, I had been using (for a few days already) a 12V-0.5A MAX, AC-DC adapter connected to the wall, for which I checked that the voltage was indeed 12V.
In my project, when the dc motor is under a load, I am measuring a voltage drop of about .6V across a 100 Ohm resistor, that is, 6 millAmp (voltage measured on the multimeter and confirmed on the Analog in PIN).
The maximum voltage that I have measured (with the multimeter) across the terminals of the dc motor is less than 10V, and I have confirmed it using a voltage divider:
acortis: @RyanfaeScotland: What do you mean by "Removing the wire from Pin 0" ?
The pins on the Arduino are numbered 0 to whatever. Pin 0 has another function named RX (maybe TX). I'm not sure why but some people have reported issues uploading sketches when there is a wire plugged into this port so if you have a circuit set up that uses this pin try removing it to see if it solves your issue.
Hello Nick,
It took me longer than I expected to connect the two arduinos together and run your sketch, but here it is. The only different thing that I see with respect to what you have on your page is
HFuse = D6 instead HFuse = DE
I have no idea of course of what that means!
Looking forward to your thoughts
The fuses look OK and the MD5 sum of the bootloader indicates you have the expected Optiboot installed. So the processor is OK, the fuses are OK, and the bootloader is installed.
Right. Can you please run the chip detector sketch (the one you ran above) on the USB chip (the other ICSP connector, near the reset button). Pay close attention to which is pin 1 (it is marked with a white dot).
Nick,
I do not have female-female jumpers handy, I will do that tomorrow. But I do not think that I have understood how to connect this second example Sorry if I am a bit slow, but can you detail the connections one more time for me? thanks
Andrea
Pin 1 is marked with a dot and the others follow as in the diagram above (top-down view, that is from above when the board is sitting on the table normally).
Can you please run the chip detector sketch (the one you ran above) on the USB chip (the other ICSP connector, near the reset button). Pay close attention to which is pin 1 (it is marked with a white dot).
You need to re-flash the ATmega16U2 chip. I haven't done this (not directly). Since your bootloader looks OK you need to put it into DFU mode and re-flash it. I suggest you look up exactly how to do that.
sorry to bother again: I as not able to reflash following the instructions there ... is there a more down to earth tutorial on how to do it. Presumably I should do it with an Arduino as an ISP programmer?