Benjamin Meyer

Important changes to forums and questions

All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.

7 years, 11 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!

Be the first to answer this question.