SX1268 failed, code -707 RadioLib SX126x Transmit Example

[safe-power]

I'm having trouble to initialize new modules. 2 modules SX1268 and 1 module LLCC68 have been tried and give error 707 Other libraries such as Arduino-LoRa-Ra01S and from Stuarts projects give similar init issues.

I've found the other reports here with error 707 but I do not understand the solutions. Any suggestions what to try next would be great.

The module is connected and connections have been triple checked as: TXEN 5, RXEN 4, MOSI 11, MISO 12, SCK 13 NSS pin: 10 DIO1 pin: 2 NRST pin: 3 BUSY pin: 9

release: 5.6.0 Arduino 1.8.19 SX1268 Ai-thinker Ra-01S module Arduino Pro-Mini- M 328, 16MHz, running on 3.3V The module fails to initialize with failed, code -707

RadioLib SX126x Transmit Example https://github.com/jgromes/RadioLib/tree/master/examples/SX126x/SX126x_Transmit

Sketch that is causing the module fail

#include <RadioLib.h>

// SX1262 has the following connections:
// NSS pin:   10
// DIO1 pin:  2
// NRST pin:  3
// BUSY pin:  9
//SX1262 radio = new Module(10, 2, 3, 9);
SX1268 radio = new Module(10, 2, 3, 9); // changed to SX1268

//TXEN 5, RXEN 4, MOSI 11, MISO 12, SCK 13  are also connected

void setup() {
  Serial.begin(9600);

  // initialize SX1262 with default settings
  Serial.print(F("[SX1268] Init... "));
    //int state = radio.begin(); -tried  failed, code -707

   int state = radio.begin(434.0, 125.0, 9, 7, 0x12, 10, 8, 1.6, false);

  if (state == RADIOLIB_ERR_NONE) {
    Serial.println(F("success!"));
  } else {
    Serial.print(F("failed, code "));
    Serial.println(state);
    while (true);
  }

... sketch truncated

--------------------------------- debug output-------------------

[SX1262] Initializing ... M SX126x
CMD 80  
DATW    0   A2  

CMD C0  
DATR    0   22  0   22  

CMD 80  
DATW    0   A2  

CMD C0  
DATR    0   22  0   22  

CMD 8F  
DATW    0   A2  0   A2  

CMD C0  
DATR    0   22  0   22  

CMD 8A  
DATW    1   A2  

CMD C0  
DATR    0   22  0   22  

CMD 93  
DATW    20  A2  

CMD C0  
DATR    0   22  0   22  

CMD 88  
DATW    3   A2  16  A2  A   A2  0   A2  0   A2  0   A2  0   A2  

CMD C0  
DATR    0   22  0   22  

CMD 2   
DATW    43  A2  FF  A2  

CMD C0  
DATR    0   22  0   22  

CMD 8   
DATW    0   A2  0   A2  0   A2  0   A2  0   A2  0   A2  0   A2  0   A2  

CMD C0  
DATR    0   22  0   22  

CMD 89  
DATW    7F  A2  

CMD 80  
DATW    0   A2  

CMD C0  
DATR    0   22  0   22  

CMD 17  
DATR    0   A2  0   0   0   0   

CMD C0  
DATR    0   22  0   22  

CMD 97  
DATW    0   A2  0   A2  1   A2  40  A2  

CMD C0  
DATR    0   22  0   22  

CMD 11  
DATR    0   A2  0   1   

CMD C0  
DATR    0   22  0   22  

Symbol length: 1.02 ms
CMD 8B  
DATW    9   A2  6   A2  3   A2  0   A2  

CMD C0  
DATR    0   22  0   22  

CMD 11  
DATR    0   A2  0   1   

CMD C0  
DATR    0   22  0   22  

CMD D   7   40  
DATW    14  A2  24  A2  

CMD C0  
DATR    0   22  0   22  

CMD 11  
DATR    0   A2  0   1   

CMD C0  
DATR    0   22  0   22  

CMD 1D  7   36  
DATR    0   A2  0   D   

CMD C0  
DATR    0   22  0   22  

CMD D   7   36  
DATW    D   A2  

CMD C0  
DATR    0   22  0   22  

CMD 8C  
DATW    0   A2  8   A2  0   A2  FF  A2  1   A2  0   A2  

CMD C0  
DATR    0   22  0   22  

CMD D   8   E7  
DATW    18  A2  

CMD C0  
DATR    0   22  0   22  

CMD 9D  
DATW    1   A2  

CMD C0  
DATR    0   22  0   22  

CMD 96  
DATW    1   A2  

CMD C0  
DATR    0   22  0   22  

CMD 98  
DATW    6B  A2  6F  A2  

CMD C0  
DATR    0   2A  0   0   

failed, code -707

[jgromes]

Since the initialization failed after image calibration (command 0x98), that would suggest either bad frequency or TCXO vs XTAL issues. 434 MHz should be fine for all SX126x devices, so the next suspect is the crystal. You set your TCXO reference voltage to 1.6V - are you sure that is correct? And does your device really have a TCXO, or just plain XTAL?

[safe-power]

And does your device really have a TCXO, or just plain XTAL?

I'm not sure how to find this out. It's a new Aliexpress module. I will connect the LLCC68 now to another Arduino to see if it fails at the same point as the SX1268.

The second radio.begin line is copied from the API example.

I would like to try out a few other settings for XTAL. Could you post an example or point me towards example radio.begin statements ?

int state = radio.begin(); -tried failed, code -707 int state = radio.begin(434.0, 125.0, 9, 7, 0x12, 10, 8, 1.6, false); code -707

[jgromes]

I'm not sure how to find this out

Step 1 is to check the documentation of the module, if there is any. If not, then trial and error - set the TCXO reference voltage to 0 and reset/power cycle the module.

int state = radio.begin(434.0, 125.0, 9, 7, 0x12, 10, 8, 0, false); 

Also, begin() without arguments expands to begin(434.0, 125.0, 9, 7, 0x12, 10, 8, 1.6, false) since those are the default values.

[safe-power]

Thank you so much. Fixed! int state = radio.begin(434.0, 125.0, 9, 7, 0x12, 10, 8, 0, false); did the trick. Both SX1268 and LLCC68 work with this setting. 2 days of my life gone, but you fixed it within 1 hour.

[jgromes]

Glad you got it working - don't hesitate to ask sooner than after two days ;)