# Major ESP8266-12E Stability Issue

I recently purchased a bare-bone ESP8266-12E module but am having major issues with stability. Here is a schematic of what I am using. I am able to program the ESP using Atmel Studio and the Arduino IDE with no issue after putting the chip into program mode by connecting GPIO0 to ground. The problem is the code never executes. I get the message:

 ets Jan  8 2013,rst cause:2, boot mode:(3,6)
load 0x4010f000, len 1384, room 16
tail 8
chksum 0x2d
csum 0x2d
v09f0c112
~ld


Indicating that the chip has entered the proper boot mode and the code should be running, but the chip freezes, doing nothing. Note: Boot mode 1 is programming mode and boot mode 3 is boot from internal flash. I assumed this was me setting up the SDK wrong or using a version with errors so I flashed the latest AT command firmware to see if the problem was in the hardware. The chip gave the same problem. A normal boot message followed by nothing. Occasional, after resetting the chip, I'd receive a stacktrace like this:

Exception (0):

ctx: sys
sp: 3ffff850 end: 3fffffb0 offset: 01a0

>>>stack>>>
3ffff9f0:  4022c0e0 00000004 3ffee734 00000001
3ffffa00:  00000001 19161310 24221f1c 2e2c2927
3ffffa10:  00002f49 3ffee6b8 4022dff4 3ffee688
3ffffa20:  3ffee688 00000000 3ffee734 3ffee688
3ffffa30:  3ffee688 3ffee734 3ffee688 00000000
3ffffa40:  3ffee688 60000600 60000200 3ffffa70
3ffffa50:  40229c2b 00000000 3ffee688 00000000
3ffffa60:  40105f02 60000e00 00000008 3fffff10
3ffffa70:  4022eda6 3ffffa80 00000008 4021e332
3ffffa80:  00000000 00000000 00000017 88a020a6
3ffffa90:  00000000 b20017e3 0000712a 3fff0b2c
3ffffaa0:  00000000 40201dcd 3fff0b2c 3fff0b2c
3ffffab0:  3ffee1fe 40233310 00000001 00000000
3ffffac0:  00000001 3fff0b2c 000002f4 003fc000
3ffffae0:  4021b534 60000e00 3fff0b2c 4021b50f
3ffffaf0:  40104eac 000003fd 00000002 60000200
3ffffb00:  3fffff10 c235e4f1 108275c5 7f3da5d8
3ffffb10:  ffff02fc ffffffff ffffffff ffffffff
3ffffb20:  ffffffff ffffffff ffffffff ffffffff
3ffffb30:  ffffffff ffffffff ffffffff ffffffff
...


During this time I am also aware that the chip was throwing off a lot of RF interference as every time this stack was printed, every device connected to wifi within a ~10m radius of the chip was disconnected and could not re-discover any network for around 10 seconds. Is it possible this chip is simply defective? Is there an issue with my power supply? I am providing the 3.3v regulator with a 5v 2A USB power brick. All of the capacitors are electrolytic.

• What is your input power source? The datasheet for the LDO mentions a drop of "1.2 V at 800 mA of load current". Make sure your power supply is not drooping. This is especially possible when using USB for input. – Pranav Apr 26 '17 at 13:58
• First thing I did was measure voltage drop across the regulator. Never got below 3.2v at any point during testing due to the large capacitor across Vcc and GND to reduce current spikes. – drew6017 Apr 27 '17 at 0:04
• I noticed the capacitors. But you can't really measure the drop with a multimeter, it's too quick for it to register on the DMM, but slow enough for the ESP to bug up. Does your ESP8266 start to heat up when this happens? If so I have encountered that once in a while as well, particularly when assembling a new breadboard circuit. I always thought it was because of bad contact on the breadboard joints. Otherwise try bootstrap resistors as on link on the left of the ESP-12F. That's guaranteed to work. – Pranav Apr 27 '17 at 16:05
• All of the connections are soldered and have been tested for continuity. There is no noticeable gain in temperature. The use of pulling resistors resulted in no change. Plus if a voltage drop were the issue, wouldn't the ESP crash repeatedly, rather than boot and stall? – drew6017 Apr 27 '17 at 20:19
• To answer the second part, ESP crashing repeatedly assumes that it is indeed booting into a mode that pulls enough current for it to crash. But if the power supply is noisy it can boot into an unreliable mode (which hasn't been documented anywhere but personally experienced by me and other members on the forum). But I just noticed I ignored a lot of detail in your question. Based on the debug messages I would suggest you've got a module with a bad flash. I presume you've already tried something simple like blink. – Pranav Apr 29 '17 at 9:24