ESP8266 Community Forum

- Wed Mar 17, 2021 8:57 pm #90875 Hello everyone,
I have a strange problem with my ESP module. After writing some code for my module and uploading it via serial the module suddenly stops to communicate after exactly 224 bytes. I've had similar oddities before and sometimes erase_flash would help. Not this time though.

I started a new Android project and copied over my program part by part, flashing it each time I add another function of the original code. Eventually the code is identical and serial communication is working again.

I edited a few more pieces in my code and communication stops. What I've noticed: When the serial port of the ESP12e module is active the LED of my FTDI connecter are lit up slightly even when not plugged in to the USB port. When the module acts weird the LED turns off, as if the entire port dies.

I've used

Code: Select alldd if=/dev/ttyUSB0 bs=1 | hexdump -C

to see whats going on:

Code: Select all00000000  72 10 02 00 6c 9c 98 72  9f 00 8c 63 02 e2 6e 80  |r...l..r...c..n.|
00000010  04 18 e0 0c 10 8c 0c 1c  82 ec 1c 70 8c 7c 8e 82  |...........p.|..|
00000020  df 00 ec 78 02 92 9f c7  92 9c e4 8c 1c 70 0c 18  |...x.........p..|
00000030  0c f2 6e 6e e4 02 84 3b  f2 6e c4 92 9c e4 0c 1b  |..nn...;.n......|
00000040  8e 0c 62 e7 24 09 72 18  02 72 18 02 70 f2 6e e0  |..b.$.r..r..p.n.|
00000050  c3 dc 00 0c 1c e0 82 87  c0 6c 1c 80 8c 9c c0 0c  |.........l......|
00000060  1c 80 0c 62 80 04 6e e2  e3 6e 80 e4 1c 92 0c 1f  |...b..n..n......|
00000070  90 0c 62 80 c4 3c 7e f2  6e ee 03 c4 c3 8c 8e 00  |..b..<~.n.......|
00000080  6c 60 13 fc 90 12 9c 23  82 6e 80 04 1c 72 18 02  |l`.....#.n...r..|
00000090  0e 02 6e 72 8e 92 9f 3b  02 84 c0 0c 7f 0c 02 87  |..nr...;........|
000000a0  3b 18 02 0e 72 9f db 92  6e 80 04 1e e0 62 9c c0  |;...r...n....b..|
000000b0  6c 60 1b c4 9e 84 0c 1f  90 ec 1c 02 92 87 03 72  |l`.............r|
000000c0  9c 3b 18 02 fc 82 6e 84  62 e0 43 6f 6e 6e 65 63  |.;....n.b.Connec|
000000d0  74 69 6e 67 20 74 6f 20  57 69 66 69 0d 0a 57 69  |ting to Wifi..Wi|


Also my code still runs in the background. It connects to Wifi and then registers to MQTT. I can send commands via MQTT and it will do whatever I programmed to do. Just no serial output anymore.

If needed, I can post the code; but I doubt it's a code issue, more something with the IDE.

For that reason I tried using PlatfromIO but eventually ended up with the same odd behavior. Here I tried running

Code: Select allpio run -t clean

to make sure any old objects are being deleted which might been in a bad state.

Has anyone else ever experienced this? And found a solution??

Flashing NodeMCU with Lua I don't have any issues with the serial communication. Only after I alter the code for a certain (unknown) amount of changes.

Thanks for any help!