ESP8266 Community Forum

- Thu Mar 30, 2017 12:00 pm #64403 I recently purchased 6x ESP-12S standalone modules from Amazon (http://a.co/av3yXJX) and I was able to program all of them but only 2 of the 6 actually work. I have a programming fixture in order to program the standalone modulse and I know it works because I was able to get the 2 working ones with my own code.

As for the other 4, they immediately throw an Exception (0) and then Watchdog Reset over and over. This even happens before I even program the module. I know this because when I hook the bare module to the console, I see AI-Thinker's console text and then it does the same Exception (0) and Watchdog Resets.

Did I really just get a bad batch of modules?

Here is the console dump for the Exception (0):

Code: Select allException (0):
epc1=0x4002f6c9 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x00000000
ctx: cont
sp: 3fff2310 end: 3fff2550 offset: 01a0
>>>stack>>>
3fff24b0:  3ffe8fd4 3fff4c9c 3fff419c 40202088
3fff24c0:  3fff24e0 3fff24d0 00000000 4020148e
3fff24d0:  0000009a 00000014 3fff4ddc 4020d6ff
3fff24e0:  3fff4e1c 00000001 3fff13f8 3fff143c
3fff24f0:  00000059 3ffea444 3fff4ddc 4020da08
3fff2500:  3fff4e04 3fff1434 3fff4ddc 4020e327
3fff2510:  3fffdad0 3fff142c 3fff1440 40210239
3fff2520:  feefeffe feefeffe feefeffe 3fff1524
3fff2530:  3fffdad0 00000000 3fff151c 40202014
3fff2540:  feefeffe feefeffe 3fff1530 40203e84
<<<stack<<<
 ets Jan  8 2013,rst cause:4, boot mode:(3,7)
wdt reset
load 0x4010f000, len 1384, room 16
tail 8
chksum 0x2d
csum 0x2d
v09f0c112

I decoded it with the Exception Decoder tool:

Code: Select allException 0: Illegal instruction
Decoding 10 results
0x40202088: optimistic_yield at ?? line ?
0x4020148e: HardwareSerial::available() at ?? line ?
0x4020d6ff: CShellInitializer::CaptureInput(unsigned char) at ?? line ?
0x4020da08: CShellInitializer::HandleConfirmation(char*) at ?? line ?
0x4020e327: CShellInitializer::RunInitializer() at ?? line ?
0x40210239: setup at ?? line ?
0x40202014: loop_wrapper() at core_esp8266_main.cpp line ?
0x40203e84: cont_norm at cont.o line ?