Hello.
There is a malfunction in my minima.
The day before it broke, it worked very well, no problem. But, the next day I plugged it back in and the rx LED was still on. And when I touched the board, what looked like a resistance near the microcontroller was very hot. Here's the photo at the bottom.
The sensor values were received from A0 and A1, but the change in the value was well detected. Literally, the sensor value increased and decreased. However, the previously output value was output about 25% lower.
It is less hot when given by USB power, and it becomes very hot when external power is added.
I use a 12V external power source connected to a power jack. I run two Arduinoes with the same auxiliary power source, one of which works strangely. There is no problem with a normal-looking Arduino being hot or getting the value strangely.
I'm upset that the board is broken, but the most important thing is that this should not happen again. I control my EV car with this because if it breaks down in the middle of running, it will be a big deal.
It works when you run these Blink examples. They turn off completely and turn on.
It works even if I passively turn off LED_RX and leave it, but after a while, the RX pin suddenly turns on.
// // the setup function runs once when you press reset or power the board
void setup() {
// // initialize digital pin LED_BUILTIN as an output.
pinMode(LED_RX, OUTPUT);
}
// // the loop function runs over and over again forever
void loop() {
digitalWrite(LED_RX, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(LED_RX, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second
}
There doesn't seem to be a problem with the coding itself. This is because RX pins are turned on even for completely empty sketches.
My guess is that the board is definitely in trouble. But, I want to know the cause for sure because this shouldn't happen again.
In summary, I connected the same external power source and only one of them broke down. It worked well the day before and suddenly broke down the next day.
Please tell me the cause