ESP8266 Community Forum

- Wed Apr 15, 2015 9:00 am #14605 First of all I would like to point out that I have read several other threads regarding ESP-01 issues. I would like to note that I already have:

- triple checked the connections
- a good 3.3V power supply (800 ma 5v to 3.3v regulator)
- a large capacitor (4700uf) near ESP-01 and a 2200uf capacitor before the regulator
- level shifting to arduino done with 2n7000 bi-directional level shifting
- tried powering the regulator with a battery pack (5v) that can easily provide more than 3A of current
- have a fairly recent firmware (AT version:0.21.0.0, SDK version:0.9.5) - I tried newer but then I could not change the baud to 9600.

Most of the time the ESP-01 work flawlessly for hours (red led is bright, blue flashing on boot and activity) and I can use it with my arduino uno to send data to a web server. Ping is also good.

However sometimes the module gets stuck and it wont boot (or reboot). It is drawing more current than usual (the red light on the module is almost off, barely visible light) and the led on my regulator is also dimmer. If i try to power down the chip (CH_PD to GND) and back on it doesn't help. Even removing power completely and giving it back wont help.
Sometimes it happens on power-on, sometimes during operation... Random...

After a while the module will start working again and it seems that nothing I do to it effects it.

Any help would be much appreciated.

- Wed Apr 15, 2015 10:55 am #14614 Also to mention: none of the pins are floating - so this should not be the cause of my problems.


When the module gets stuck, this is what i get on the serial monitor (baud 115200):

Code: Select allatal exception (0):
epc1=0x4020eb20, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Ftal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fdal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, epc=0x00000000
!l exception 0):
 ecpton():8, epc2=0x00000 ep3=0x00000 ecaddr0x000000, epc=x0000000, depc0x0000000
 ecpin 0: epc=0x02018, pc=0000000 ec30x00000 xcadr0x00000 dep=x00000
 xcpto ():c=x42088,ep2=x00000 ec30x00000 xcadr=x00000 dpc000000
 xcpin(0: pc=x0000,ec3000000 xvad=x0000,dec0000000000, ec=x00000
� ecpin : p2000000 ec=x0000,exvdr0x0000dp=x000000,dp=000000 xcpto 0:
� 8etin 0:2000000 ec=8000 ,eHvdr0X0000,dp=x0000,dEc000000 xcpto 0:
          `c=x42084 pC=x000,e#300000 xvAd=80000,dEc0000 �@�Y��
lec0iO  :                                                     �'!\�KL��184  2 x0000,Ec= 0000, XfadB0 0   e#@000
         Ec=x18,%c=x000  pC= 000,e#Vdb0000 ,deC   


Normal boot looks like this:

Code: Select allets Jan  8 2013,rst cause:4, boot mode:(3,7)

wdt reset
load 0x40100000, len 816, room 16
tail 0
chksum 0x8d
load 0x3ffe8000, len 788, room 8
tail 12
chksum 0xcf
ho 0 tail 12 room 4
load 0x3ffe8314, len 288, room 12
tail 4
chksum 0xcf
csum 0xcf

2nd boot version : 1.2
  SPI Speed      : 40MHz
  SPI Mode       : QIO
  SPI Flash Size : 4Mbit
jump to run user1



- Wed Apr 15, 2015 11:37 am #14620 My ESP was doing exactly the same. It was starting the reboot loop and waiting the end of the ages.

After many tryes it worked using 220uF caps in the 3,3V and 5V sides.
I also pulled up GPIOs with "strong" 2,2k resistors and kept reset pin floating.

Last edited by uber4 on Thu Apr 16, 2015 1:10 am, edited 1 time in total.

- Wed Apr 15, 2015 5:11 pm #14654 What voltage regulator are you using?
I struggled with AMS1117 3.3V. Most of the time it worked, but sometimes ESP just went crazy.

I am now trying with a buck converter based on LM2596S that can provide 3A peak current (I set output voltage to 3.37V - just slightly higher than 3.3V to compensate for drops) and also some capacitors. I have done limited testing, but so far it is much better.