ESP8266 Community Forum

- Thu Jan 25, 2018 7:03 am #73476 When it is in bootloader/flashing mode. it doesn't require as high a current compared to when it uses the transmitter. One of the things it does when it executes a program is to calibrate the RF section and it can draw a lot of current for that process. And if you get too much of a voltage dip the cpu crashes. You never get a chance to get to your code. So it looks to you like the flashing process didn't work but really it is that it dies when it tries to run.

This is not an easy processor to work with. It is claimed to be low power, and on average it can be. But it can draw in excess of 1/2 an amp for brief periods. So the power supply must be able to handle that.

- Thu Jan 25, 2018 7:23 am #73477 Do not use busy pins in your sketch? Give some example of your program please.

- Thu Jan 25, 2018 4:52 pm #73488 Hi guys,

I just came home and tried to upload the following sketch but it didn't work.

Code: Select all#include <Arduino.h>

void setup()
{
    Serial.begin(74880);
    Serial.println("Starting ...");
    pinMode(4, OUTPUT);
}

void loop()
{
    digitalWrite(4, HIGH);
    delay(25);
    digitalWrite(4, LOW);
    delay(25);
}


So, I put the 100uF capacitor near to the Vcc and Gnd pins as you can see here. (props to rudy)
I manage to put it working on my first attempt. I really think it was a beginner's luck.
The circuit is consuming about 70mA just to blink the green led. Is this OK?
I'll leave the circuit working for a few hours before try another uploading just to ensure my theory about time/temperature is totally wrong.
As rudy told I think the problem is related the power supply. I need to investigate other options.
Thank you guys.
Regards,

LA

- Thu Jan 25, 2018 8:16 pm #73495 That's better than before but it could be better yet. I solder direct to the ESP-12E module's pins. Trace length matter. Those white boards are really cheap but total crap. Poorly executed pcb. But I hope what you have will get you up and running without the instability you had.

Oh, and at 70mA average current it is unlikely that would be causing any heat based issues.