ESP8266 Community Forum

- Tue Dec 27, 2016 2:51 pm #60029 I have 2 ESP-12E boards I bought on Amazon (from Maker Focus). I have it plugged in to my laptop via USB. The first board was continiously not working properly it seems like it would just reboot every few seconds. While attempting to troubleshoot I somehow (not sure exactly) fried the board ( I could smell it).

I was trying to use a very script:

Code: Select all

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin 13 as an output.
  Serial.begin(115200);
  Serial.println("Welcome");
  Serial.flush();
  pinMode(D2, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
  Serial.println("Test1");
  Serial.flush();
  digitalWrite(D2, HIGH);   // turn the LED on (HIGH is the voltage level)
  Serial.println("High");
  Serial.flush();
  delay(100);              // wait for a second
  digitalWrite(D2, LOW);    // turn the LED off by making the voltage LOW
  Serial.println("Low");
  Serial.flush();
  delay(100);              // wait for a second
  Serial.println("Test2");
  Serial.flush();
}

But it kept rebooting and the LED wouldn't flicker consistently. I was guessing it might be related to the input voltage from the USB, but before I try again with my (last) board I wanted to find out if my laptop USB port is a valid output of power for the board?

Link to the actual boards:
https://www.amazon.com/Makerfocus-ESP82 ... B01IK9GEQG

- Tue Dec 27, 2016 7:33 pm #60036 Hi, unless you had it on a metal surface you should have been fine. The constant reset sugests a drop in power of some type. I think you just had a bad board, at a real push (don't try it) the ESP will run on 5V, so it was some other component on the board that fried.

- Tue Dec 27, 2016 7:59 pm #60039 So in theory I could try to salvage the ESP itself right? Not sure its worth it for the cost.

I think your bad board theory is correct. I tried the same approach and things seemed to work just fine.

- Wed Dec 28, 2016 12:06 am #60044 If you smelled it then the board probably won't work again. The usb port should not have been a problem. If you have the wrong voltage coming out then your laptop would probably not be working properly.

I would try plugging in something else into the laptop before you try your last board. If you have a voltmeter I would say plug in the bad board and see what the voltage from the 5 volt line to circuit ground (or -ve, depending on how it's marked). It might be lower than 5 volts now with the bad board plugged in. It should not be higher than 5 volts. If it is then you do have a problem with your laptop.

Do you have any other devices to plug into the usb port. Like a memory stick? See if it works. I would also look at the cable and check to see if it is OK. But I probably wouldn't use it at this point. Not until you have a better idea of where the problem is.