Support request for UNO r3 + SX1272MB2xAS on 868 freq

[maitrekobayashi]

Hi, I'm new to embedded programmation and I'm currently facing an issue on my UNO R3 + SX1272 configuration. (objenious network, 868MHz, France) I'm working with the ttn-otaa given example.

I set the right parameters on lmic_project_config.h : **#define CFG_eu868 1

define CFG_sx1272_radio 1**

The console returns : Starting FAILURE C:...\Arduino\libraries\MCCI_LoRaWAN_LMIC_library\src\lmic\oslmic.c:53

which lead to this function :

*void os_init() { if (os_init_ex((const void )&lmic_pins)) return; ASSERT(0); }**

I'm working with Arduino IDE 1.8.13, and i add #define DISABLE_PING in the main.

Any idea of what the problem could be ? Maybe the UNO R3 do not fit ? Thanks

[terrillmoore]

You'd get a failure other places if it didn't fit. You should add DISABLE_PING (and DISABLE_BEACONS) in your lmic_project_config.h; but this failure is due to os_init_ex() not liking your lmic_pins object, and that's much lower level. Can you look at the code for os_init_ex() and find the paths that will return false, and add ASSERT(0) in each place until you track it down?

[maitrekobayashi]

Hi, thanks for answering,

I tried to track down the error, and it led me to C:...\Arduino\libraries\MCCI_LoRaWAN_LMIC_library\src\lmic\radio.c:1164 which is :

_u1_t radio_rand1 () { u1_t i = randbuf[0]; ASSERT( i != 0 ); if( i==16 ) { os_aes(AES_ENC, randbuf, 16); // encrypt seed with any key i = 0; } u1t v = randbuf[i++]; randbuf[0] = i; return v; ASSERT(0); }

I added _#define DISABLEBEACONS and _#define DISABLEPING in my lmic_project_config.h I also tried to verify that radio_init() called in os_init_ex() was ok but unsuccessfully

[maitrekobayashi]

But I feel I didn't catch how to use properly ASSERT(0); So I added many in the code of os_init_ex and I got :

_int os_init_ex (const void *pintable) { ASSERT(0); have a return of this line memset(&OS, 0x00, sizeof(OS)); ASSERT(0); have a return of this line hal_init_ex(pintable); ASSERT(0); have a return of this line if (! radio_init()) return 0;; ASSERT(0); DON'T have a return of this line LMIC_init(); ASSERT(0); DON'T have a return of this line return 1;; }

void os_init() { if (os_init_ex((const void *)&lmicpins)) return; ASSERT(0); }

[terrillmoore]

It appears that radio_init() is failing.

Almost always, this is because of a wiring problem. How is your SX1272 connected to your UNO?

Best regards, -Terry

[maitrekobayashi]

Hi again , I might have found the problem, which was a pinmapping one : The .nss pin of the transceiver was supposed to be linked to the 6th pin of the Uno, but in my case I'm using a semtech shield which physically connect the .nss pin of the SX1272 to the 10th pin of the UNO R3.

const lmic_pinmap lmic_pins = { //.nss = 6, //NOT WORKING .nss = 10, .rxtx = LMIC_UNUSED_PIN, .rst = 5, .dio = {2, 3, 4}, };

Thanks for your time and advices,

Best Regards