Problem with nodeMCU Devkit 1.0


I’ve just got myself a nodeMCU devkit 1.0 (esp-12e), and trying to test it. I made a very simple sketch that connects to blynk and prints to serial every 1 second that it is still running.

but im getting some errors im not familiar with. as soon as i uncomment Blynk.begin(auth, "SSID", "PWD");
all is running fine with no problems. Anyone who can tell me whats wrong?

0‚~?–4û!ƒ{ƒOAaû[213] Connecting to *******
[6229] Connected to WiFi
[6229] Blynk v0.3.0
[6229] Connecting to
Still Running
[6454] Ready (ping: 3ms).
Still Running
Still Running
Still Running
Still Running
Still Running
Still Running
Still Running
Still Running
Still Running

Exception (0):
epc1=0x40217599 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x00000000

ctx: sys 
sp: 3ffffdc0 end: 3fffffb0 offset: 01a0

3fffff60:  00000000 40210af1 3ffec96e 40217185  
3fffff70:  3ffeef38 3ffec958 000000f5 3ffeb490  
3fffff80:  00000000 3ffeef38 00000000 3fffdcb0  
3fffff90:  40216b78 3fffdab0 00000000 3fffdcc0  
3fffffa0:  3ffeb490 40000f49 3fffdab0 40000f49  
ÿ¼ÔL¤<Φêÿ[211] Connecting to *********

Exception (0):
epc1=0x4000ac6f epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x00000000

ctx: sys 
sp: 3ffff8dü!ãL¤<1¤ñþ[210] Connecting to ********

My code

#define BLYNK_PRINT Serial    // Comment this out to disable prints and save space
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>

char auth[] = "2b65f096df0d4d2087358254c6b8f275";

int i = 0;
unsigned long lastMillis;

void setup()
//  Blynk.begin(auth, "SSID", "PWD");

void loop()

  if(millis() - lastMillis > 1000)
    lastMillis = millis();
  Serial.println("Still Running");
  i = 0;

If you don’t do Blynk.begin, but you are doing, you can expect some unexpected behaviour. You need to start Blynk with Blynk.begin.

It’s like you try to drive your car without starting it first.

sorry… i can see what i wrote was some mess.

What i ment was:
When i’m running the sketch with blynk.begin(), all the errors appears. As soon as i comment blynk.begin() out, i have no errors.

Have you confirmed the nodemcu is stable? A friend just went through a weekend trying a bunch of suggestions get his to stop randomly reseting. He reports a different USB cable did the trick. I’ve never used one, just mentioning his stability issues (which I wouldn’t have expected).

Actually i didn’t. I stopped testing when i found out that removing the Blynk part “appearantly” fixed the problem.

But not to say that it could’t be the case for me to. So i will definitely try some more. I was just under the impression that nodeMCU should be quite stable?

Thanks anyway, i will start with the usb cable and other possibilities.

Right, that was exactly my reaction. Here I was suggesting to him to go with a nodemcu to avoid troubles I’ve worked through, only to have his own. I’d go back to basics, power, decoupling, connections, etc…

Funny aside, just yesterday I was heating some shrink wrap around a new connector, only to find that the piezo starter (or some such) on the lighter was causing all ESPs in a 1m range to restart…