I hooked my Analog Pin to a power source after the power source was turned on. Worked like a charm. Then I switched my power source off and on. Now, the Analog Pin is stuck at a value indiscriminately of input wire voltages. If I hook the Analog Pin up to GND, it offsets the value by around 2 volts but stays stuck at that starting value. I'm guessing when I switched the power on, there was an initial power spike when the power source turned on that led to an overvoltage on the end of the Analog Pin. I could really use help here, I'm afraid I just fried my controller. Any help would be appreciated. Thank you!
Agreed. We have all made similar mistakes, so consider it part of the trade.
Perhaps that one pin is the only one that is burned. Check to see if you can load the "blink" program, and if that works, try another analog pin.
Hint: it helps to place a 10K resistor between the voltage source you are measuring and the analog input pin. That won't affect normal readings, but could possibly save the Arduino from similar overvoltage catastrophes.
Perhaps that one pin is the only one that is burned. Check to see if you can load the "blink" program, and if that works, try another analog pin.
- The blink program works great!
- Other Analog Pins WERE working after I fried the initial pin. The thing is, after I fried the initial pin, panicked I went troubleshooting by trying out things on all the pins. The good news: I eventually deduced that the overvoltage was destroying the pins. Bad news: I did this by destroying all my pins.
I'm kind of facepalming for doing this to all my pins, but, at the same time, if even one pin is destroyed permanently, I'm going to need a new controller. I'll order some 10k resistors right away.
Is there anything I can do to... unfry these pins...?
Sadly, once fried, the Arduino is usually headed for the recycle bin.
If you have the Uno, you can replace the socketed ATmega328 chip with a new one. They are cheap (buy from a reputable distributor to avoid fakes), but you probably will have to burn the bootloader.
Plenty of tutorials on line for that.
I've been happy with these cheap Arduino Pro Minis from eBay, and I've never had one dead on arrival. Buy five at a time in case you fry another one. The 3.3V ones are especially convenient, because they can be connected directly to 3.3V sensors (with 5V Arduinos, you need a level shifter):
Thank you very much for your help. I've ordered pro minis, voltometers, and resistors to make sure the same doesn't happen again. Happy holidays!
If you destroyed all of the pins the board is still good as a template for mounting other boards. If only the analog is bad you can still use the digital part but mark the board so you know after it gets mixed with other boards. You will not be the only one with a template, I have several.