Benjamin Meyer

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8 years, 6 months ago.

LMiC bug

Hello everyone!

I am currently testing the LMiC App (code LoRaWAN-lmic-app from Semtech) with the NUCLEO-L073RZ board and the SX1276MB1MAS shield.

I noticed that the program occasionally get stuck so I decided to add some debug lines to figure it out. The program is always stuck between the sending of a frame and the check of the last RX window.

Here is the modified piece of code for debugging:

//======================================== Data frames

// Fwd decl.
static bit_t processDnData(void);

static void processRx2DnDataDelay (xref2osjob_t osjob) {
    pc_lmic.printf("?\r\n");
    processDnData();
}

static void processRx2DnData (xref2osjob_t osjob) {
    pc_lmic.printf("? ");
    if( LMIC.dataLen == 0 ) {
        LMIC.txrxFlags = 0;  // nothing in 1st/2nd DN slot
        // Delay callback processing to avoid up TX while gateway is txing our missed frame! 
        // Since DNW2 uses SF12 by default we wait 3 secs.
        pc_lmic.printf("RX2 delayed");
        os_setTimedCallback(&LMIC.osjob,
                            (os_getTime() + DNW2_SAFETY_ZONE + rndDelay(2)),
                            processRx2DnDataDelay);
        return;
    }
    processDnData();
}


static void setupRx2DnData (xref2osjob_t osjob) {
    pc_lmic.printf("RX2");
    LMIC.osjob.func = FUNC_ADDR(processRx2DnData);
    setupRx2();
}


static void processRx1DnData (xref2osjob_t osjob) {
    pc_lmic.printf("? ");
    if( LMIC.dataLen == 0 || !processDnData() )
        schedRx2(DELAY_DNW2_osticks, FUNC_ADDR(setupRx2DnData));
}


static void setupRx1DnData (xref2osjob_t osjob) {
    pc_lmic.printf("RX1");
    setupRx1(FUNC_ADDR(processRx1DnData));
}


static void updataDone (xref2osjob_t osjob) {
    pc_lmic.printf("[LMIC] Check RX windows... ");
    txDone(DELAY_DNW1_osticks, FUNC_ADDR(setupRx1DnData));
}

// ========================================

Here is the result:

[MAIN] Preparing TX frame...
[MAIN] PORT = 0000000F
[MAIN] DATA SIZE = 00000008
[MAIN] FRAME = 01 00 04 00 03 FF A9 24
[LMIC] Looking for another suitable channel... Done! (TX on channel 2 in 84.2 s)
[LMIC] Frame sent with DR0 (SeqNoUp = 00000005)
[LMIC] Check RX windows... RX1? RX2? RX2 delayed?
[LMIC] Looking for another suitable channel... Done! (TX on channel 0 in 140.9 s)
[LMIC] Frame sent with DR0 (SeqNoUp = 00000005)
[LMIC] Check RX windows... RX1? RX2? RX2 delayed?
[LMIC] Looking for another suitable channel... Done! (TX on channel 1 in 140.1 s)
[LMIC] Frame sent with DR0 (SeqNoUp = 00000005)
[LMIC] Check RX windows... RX1? RX2? RX2 delayed?
[LMIC] Looking for another suitable channel... Done! (TX on channel 2 in 139.9 s)
[LMIC] Frame sent with DR0 (SeqNoUp = 00000005)
[LMIC] Check RX windows... RX1? RX2? RX2 delayed?
[LMIC] Looking for another suitable channel... Done! (TX on channel 0 in 140.5 s)
[LMIC] Frame sent with DR0 (SeqNoUp = 00000005)
[LMIC] Check RX windows... RX1? RX2? RX2 delayed?
[LMIC] Looking for another suitable channel... Done! (TX on channel 1 in 139.5 s)
[LMIC ] Frame sent with DR0 (SeqNoUp = 00000005)
[LMIC] Check RX windows... RX1

// Program stuck

The problem is consequently in the setupRx1() function, which apparently does not call the processRx2DnData job. I noticed that the data processing job was treated separately for the RX2 window and I tried to use the same process for RX1 but this time the programm got stuck by RX2. Then I tried to apply the RX1 process to RX2 but without success...

I would like to know if any of you had this problem and fixed it or if someone could see where the error could be.

Thank you!

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