RFM95W + ESP32C3 - join error -5

[michapr]

Hi,

I have no idea what I made wrong, maybe somebody can help?

Have connected the ESP32C3 with RFM95W module, module is recognized, I see the join in TTN but get an join error -5
What maybe missing here?

Code is LoRaWAN_Starter.ino with custom SPI settings:

#ifndef _CONFIG_H
#define _CONFIG_H

#include <RadioLib.h>
#include <SPI.h>

#define SX1276_CS 7
#define SX1276_SCK 8
#define SX1276_MOSI 6
#define SX1276_MISO 5
#define SX1276_RESET 9
#define SX1276_BUSY 1
#define SX1276_DIO1 2

const uint32_t uplinkIntervalSeconds = 5UL * 60UL;    // minutes x seconds

#define RADIOLIB_LORAWAN_JOIN_EUI  0x00000000xxxxxxxx
#define RADIOLIB_LORAWAN_DEV_EUI   0x70B3D57Exxxxxxxx
#define RADIOLIB_LORAWAN_APP_KEY   0x74, ... 
#define RADIOLIB_LORAWAN_NWK_KEY   0x9F, ... 

const LoRaWANBand_t Region = EU868;
const uint8_t subBand = 0;  // For US915, change this to 2, otherwise leave on 0

SX1276 radio = new Module(SX1276_CS, SX1276_DIO1, SX1276_RESET, SX1276_BUSY);

uint64_t joinEUI =   RADIOLIB_LORAWAN_JOIN_EUI;
uint64_t devEUI  =   RADIOLIB_LORAWAN_DEV_EUI;
uint8_t appKey[] = { RADIOLIB_LORAWAN_APP_KEY };
uint8_t nwkKey[] = { RADIOLIB_LORAWAN_NWK_KEY };

LoRaWANNode node(&radio, &Region, subBand);

// helper function to display any issues
void debug(bool isFail, const __FlashStringHelper* message, int state, bool Freeze) {
  if (isFail) {
    Serial.print(message);
    Serial.print("(");
    Serial.print(state);
    Serial.println(")");
    while (Freeze);
  }
}

// helper function to display a byte array
void arrayDump(uint8_t *buffer, uint16_t len) {
  for(uint16_t c = 0; c < len; c++) {
    char b = buffer[c];
    if(b < 0x10) { Serial.print('0'); }
    Serial.print(b, HEX);
  }
  Serial.println();
}

#endif

/*
  RadioLib LoRaWAN Starter Example

  This example joins a LoRaWAN network and will send
  uplink packets. Before you start, you will have to
  register your device at https://www.thethingsnetwork.org/
  After your device is registered, you can run this example.
  The device will join the network and start uploading data.

  Running this examples REQUIRES you to check "Resets DevNonces"
  on your LoRaWAN dashboard. Refer to the network's 
  documentation on how to do this.

  For default module settings, see the wiki page
  https://github.com/jgromes/RadioLib/wiki/Default-configuration

  For full API reference, see the GitHub Pages
  https://jgromes.github.io/RadioLib/

  For LoRaWAN details, see the wiki page
  https://github.com/jgromes/RadioLib/wiki/LoRaWAN

*/

#include "config.h"

void setup() {
  Serial.begin(115200);
  SPI.begin(SX1276_SCK, SX1276_MISO, SX1276_MOSI, SX1276_CS);
  Serial.printf("SPI.begin(SCK=%d, MISO=%d, MOSI=%d, CS=%d)\n", SX1276_SCK, SX1276_MISO, SX1276_MOSI, SX1276_CS);
  SPI.setFrequency(4000000);

  delay(5000);  // Give time to switch to the serial monitor
  Serial.println(F("\nSetup ... "));

  Serial.println(F("Initalise the radio"));
  int state = radio.begin();
  debug(state != RADIOLIB_ERR_NONE, F("Initalise radio failed"), state, true);

  Serial.println(F("Join ('login') to the LoRaWAN Network"));
  state = node.beginOTAA(joinEUI, devEUI, nwkKey, appKey, true);
  debug(state < RADIOLIB_ERR_NONE, F("Join failed"), state, true);
  Serial.println(F("Ready!\n"));
}


void loop() {
  Serial.println(F("Sending uplink"));

  // Read some inputs
  uint8_t Digital1 = digitalRead(2);
  uint16_t Analog1 = analogRead(3);

  // Build payload byte array
  uint8_t uplinkPayload[3];
  uplinkPayload[0] = Digital1;
  uplinkPayload[1] = highByte(Analog1);   // See notes for high/lowByte functions
  uplinkPayload[2] = lowByte(Analog1);
  
  // Perform an uplink
  int state = node.sendReceive(uplinkPayload, sizeof(uplinkPayload));    
  debug((state != RADIOLIB_LORAWAN_NO_DOWNLINK) && (state != RADIOLIB_ERR_NONE), F("Error in sendReceive"), state, false);

  Serial.print(F("Uplink complete, next in "));
  Serial.print(uplinkIntervalSeconds);
  Serial.println(F(" seconds"));
  
  // Wait until next uplink - observing legal & TTN FUP constraints
  delay(uplinkIntervalSeconds * 1000UL);  // delay needs milli-seconds
}

Log:

20:26:38.182 -> 
20:26:38.182 -> Setup ... 
20:26:38.182 -> Initalise the radio
20:26:38.182 -> RLB_DBG: RadioLib Debug Info
20:26:38.182 -> RLB_DBG: Version:  6.5.0.0
20:26:38.182 -> RLB_DBG: Platform: ESP32
20:26:38.182 -> RLB_DBG: Compiled: Apr 11 2024 20:55:02
20:26:38.182 -> 
20:26:38.182 -> RLB_DBG: M	SX127x
20:26:38.182 -> Join ('login') to the LoRaWAN Network
20:26:38.182 -> RLB_PRO: Configuration mismatch (checksum: 0, mode: 0, class: 0, plan: 1)
20:26:38.182 -> RLB_PRO: Nonces buffer:
20:26:38.182 -> RLB_PRO: 0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | ................
20:26:38.182 -> RLB_PRO: Clearing buffer and starting fresh
20:26:38.182 -> RLB_PRO: Setting up dynamic channels
20:26:38.182 -> RLB_PRO: UL:   0 1 868.100 (0 - 5) | DL:   0 1 868.100 (0 - 5)
20:26:38.182 -> RLB_PRO: UL:   1 1 868.300 (0 - 5) | DL:   1 1 868.300 (0 - 5)
20:26:38.182 -> RLB_PRO: UL:   2 1 868.500 (0 - 5) | DL:   2 1 868.500 (0 - 5)
20:26:38.182 -> RLB_PRO: [MAC] 0x03
20:26:38.182 -> RLB_PRO: 0000000 20 00 00 80                                     |  ...              
20:26:38.182 -> RLB_PRO: LinkADRReq: dataRate = 2, txSteps = 0, chMask = 0x0000, chMaskCntl = 0, nbTrans = 0
20:26:38.182 -> RLB_PRO: PHY: SF = 10, BW = 125.000 kHz, CR = 4/5
20:26:38.182 -> RLB_PRO: PHY: TX = 16 dBm
20:26:38.182 -> RLB_PRO: LinkADRAns: status = 0x07
20:26:38.182 -> RLB_PRO: [MAC] 0x04
20:26:38.182 -> RLB_PRO: 0000000 07                                              | .                 
20:26:38.182 -> RLB_PRO: DutyCycleReq: max duty cycle = 1/2^7
20:26:38.182 -> RLB_PRO: [MAC] 0x05
20:26:38.182 -> RLB_PRO: 0000000 00 d2 ad 84                                     | ....              
20:26:38.182 -> RLB_PRO: RXParamSetupReq: rx1DrOffset = 0, rx2DataRate = 0, freq = 869.525024
20:26:38.182 -> RLB_PRO: RXParamSetupAns: status = 0x07
20:26:38.182 -> RLB_PRO: [MAC] 0x08
20:26:38.182 -> RLB_PRO: 0000000 01      
20:26:38.182 -> RLB_PRO: RXTimingSetupReq: delay = 1 sec
20:26:38.182 -> RLB_PRO: [MAC] 0x09
20:26:38.182 -> RLB_PRO: 0000000 05                                              | .                 
20:26:38.182 -> RLB_PRO: TxParamSetupReq: dlDwell = 0, ulDwell = 0, maxEirp = 16 dBm
20:26:38.182 -> RLB_PRO: [MAC] 0x0C
20:26:38.182 -> RLB_PRO: 0000000 65                                              | e                 
20:26:38.182 -> RLB_PRO: ADRParamSetupReq: limitExp = 6, delayExp = 5
20:26:38.182 -> RLB_PRO: [MAC] 0x0F
20:26:38.182 -> RLB_PRO: 0000000 fa                                              | .                 
20:26:38.182 -> RLB_PRO: RejoinParamSetupReq: maxTime = 15, maxCount = 10
20:26:38.182 -> RLB_PRO: RejoinParamSetupAns: status = 0x03
20:26:38.230 -> RLB_PRO: 
20:26:38.230 -> RLB_PRO: PHY: Frequency UL = 868.100 MHz
20:26:38.230 -> RLB_PRO: PHY: SF = 10, BW = 125.000 kHz, CR = 4/5
20:26:38.803 -> RLB_PRO: Join-request sent <-- Rx Delay start
20:26:38.803 -> Join failed(-5)

TTN:

Maybe somebody have any idea?
THANKS!

[jgromes]

-5 is RADIOLIB_ERR_TX_TIMEOUT so my guess is bad wiring on the DIO0 pin. That seems further supported by this part of your code:

#define SX1276_BUSY 1
#define SX1276_DIO1 2

RFM9x/SX127x does not have a BUSY pin, so I don't know what's going on there.

[michapr]

SX1276_BUSY is DIO0 of RFM95W.
So I think the wiring is right, have checked and changed several times...

[jgromes]

In that case, you have DIO0 and DIO1 swapped. Your constructor looks like this:

SX1276 radio = new Module(SX1276_CS, SX1276_DIO1, SX1276_RESET, SX1276_BUSY);

However, SX127x constructor expects this (as shown in the examples):

// SX1278 has the following connections:
// NSS pin:   10
// DIO0 pin:  2
// RESET pin: 9
// DIO1 pin:  3
SX1278 radio = new Module(10, 2, 9, 3);

[michapr]

THANKS!
Yes,... this was the issue. I made the mistake at the very beginning - and then repeated it with every subsequent attempt... Embarrassing

[HeadBoffin]

SX1276_BUSY is DIO0 of RFM95W.

It's not good practise to name things like this - on the SX127x range it's very definitely DIO0, it's only BUSY on the SX126x range. I can see where you were coming from, but it caused our esteemed leader pause, it passed me by at first read and it could have been a much longer debugging affair!

[michapr]

Sorry. I have before connected a SX126x device, that's why... Will change next time before asking for help.

[jgromes]

@HeadBoffin your esteemed leader does not really mind ;) Also TX timeout is nearly universally incorrect wiring, I will update the troubleshooting guide accordingly. And on a final note, the LR11x0 devices actually use the naming convention of DIO0 = BUSY, which I'm sure will confuse some people in the future.

@michapr glad you got it working!