Looking for help with ESP32 + SX1276

iijao-balloon
Wed, 28 Jan 2026 11:13:17 +0000

Hey,

this is my first post, don’t know if I’m here right, but I can’t create a new topic and ask because of that here.

I tried yesterday to register an ESP32 S3 Cam with SX1276 in TTN, but the OTAA didn’t work. Here information, I hope I mention all relevant.

I wanted to use the OAAT example sketch of the MCCI LoRaWAN LMIC Library by IBM, Matthijs Kooijman, Terry Moore, ChaeHee Won, Frank Rose, Tristan Weber. I personalized it, see the uploaded sketch.

But it doesn’t work, this is the serial output:

Starting
FAILURE
/home/david/Arduino/libraries/MCCI_LoRaWAN_LMIC_library/src/hal/hal.cpp:38
Guru Meditation Error: Core  1 panic'ed (Interrupt wdt timeout on CPU1).

Core  1 register dump:
PC      : 0x42002a58  PS      : 0x00060d34  A0      : 0x82002a99  A1      : 0x3fcebe60
A2      : 0x3c0302dd  A3      : 0x00000026  A4      : 0x3fc984e8  A5      : 0x3fc94990
A6      : 0x00000000  A7      : 0x3fc98190  A8      : 0x82002a58  A9      : 0x3fcebe40
A10     : 0x3fc98190  A11     : 0x00000026  A12     : 0x0000000a  A13     : 0x00060523
A14     : 0x00000000  A15     : 0x00000002  SAR     : 0x0000000f  EXCCAUSE: 0x00000006
EXCVADDR: 0x00000000  LBEG    : 0x400556d5  LEND    : 0x400556e5  LCOUNT  : 0xffffffff


Backtrace: 0x42002a55:0x3fcebe60 0x42002a96:0x3fcebe80 0x42002b4d:0x3fcebea0 0x42004e63:0x3fcebec0 0x42004e7a:0x3fcebee0 0x420022ef:0x3fcebf00 0x42008b71:0x3fcebf30 0x4037be1d:0x3fcebf50


Core  0 register dump:
PC      : 0x40378806  PS      : 0x00060334  A0      : 0x8202895c  A1      : 0x3fc9f920
A2      : 0x00000000  A3      : 0x00000000  A4      : 0x00060020  A5      : 0x3fc9f1f0
A6      : 0x00000001  A7      : 0x00000160  A8      : 0x8200bdf2  A9      : 0x3fc9f8e0
A10     : 0x00000000  A11     : 0x00000000  A12     : 0x3fc95320  A13     : 0x00000000
A14     : 0x00060020  A15     : 0x3fc9f8ff  SAR     : 0x00000019  EXCCAUSE: 0x00000006
EXCVADDR: 0x00000000  LBEG    : 0x00000000  LEND    : 0x00000000  LCOUNT  : 0x00000000


Backtrace: 0x40378803:0x3fc9f920 0x42028959:0x3fc9f940 0x4037cf73:0x3fc9f960 0x4037be1d:0x3fc9f980




ELF file SHA256: c61fe3e90

Guru Meditation Error: Core  1 panic'ed (Interrupt wdt timeout on CPU1).

Core  1 register dump:
PC      : 0x403845cf  PS      : 0x00020434  A0      : 0x82015493  A1      : 0x3fcebcb0
A2      : 0x00020423  A3      : 0xa5a5a5a5  A4      : 0x82015493  A5      : 0x00060425
A6      : 0xfffbfff0  A7      : 0x00000076  A8      : 0x820153b1  A9      : 0x3fcebc80
A10     : 0x00000000  A11     : 0x3fcebc9b  A12     : 0x00000001  A13     : 0x3fcebc9c
A14     : 0x3fc986b4  A15     : 0x60038000  SAR     : 0x00000006  EXCCAUSE: 0x00000006
EXCVADDR: 0x00000000  LBEG    : 0x400570e8  LEND    : 0x400570f3  LCOUNT  : 0x00000000


Backtrace: 0x403845cc:0x3fcebcb0 0x42015490:0x3fcebcc0 0x42028e1d:0x3fcebce0 0x420067f0:0x3fcebd10 0x4200c521:0x3fcebd30 0x40375cb9:0x3fcebd80 0x40375f60:0x3fcebda0 0x00040022:0x3fcebe60 |<-CORRUPTED

I’ve connected the board like the following:

ESP32 S3 | SX1276
2 | DIO0
14 | RESET
21 | NSS/CS
45 | SCK
46 | MISO
47 | MOSI

Like written in the Code, I changed the file /Arduino/libraries/MCCI_LoRaWAN_LMIC_library/project_config/lmic_project_config.h, I uploaded it, too.

I hope, that is enough information and you could help me.

ttn_otaa.ino (8,3 KB)

lmic_project_config.h (415 Bytes)

Thank you, and if somebody is interested about the project (altitude controllable weather balloon), just say, I can write a weekly newsletter or something similiar…
PS: I always get update notifications in the arduino IDE for ESP32 boards, but if fails:
Failed to update esp32. Error: 4 DEADLINE_EXCEEDED: context deadline exceeded (Client.Timeout or context cancellation while reading body)