CubeCell Lora P2P, peer-to-peer, wake-up after LowPower_Handler() function

#1

Please, advise how can I resume the Lora P2P, peer-to-peer, transmission after the LowPower_Handler(); function? If I comment-out this one line - //LowPower_Handler(); the transmission works fine (see the code below).

If I un-comment it, the Lora transmission stops after 6 successful messages. And I cannot figure out how I can wake it up.

With the GPIO7 pin and RST pins I can stop and resume transmission all right. But I could not do it yet with the timer. The example LowPower_WakeUpByTimer works fine by itself, and it works fine with my BME680 sensor. The CubeCell board goes to sleep after 6 LowPower_Handler(); runs, than it wakes up, and the sensor works OK.

I guess I should, probably, add some code which re-initializes Lora.

#include "Arduino.h"
#include "LoRaWan_APP.h"

#define timetosleep 5000
#define timetowake 15000
static TimerEvent_t sleep;
static TimerEvent_t wakeup;
boolean lowpower = true;

#ifndef LoraWan_RGB
#define LoraWan_RGB 0
#endif

#define RF_FREQUENCY 868000000 // Hz

#define TX_OUTPUT_POWER 14 // dBm

#define LORA_BANDWIDTH 0 // [0: 125 kHz,
// 1: 250 kHz,
// 2: 500 kHz,
// 3: Reserved]
#define LORA_SPREADING_FACTOR 7 // [SF7…SF12]
#define LORA_CODINGRATE 1 // [1: 4/5,
// 2: 4/6,
// 3: 4/7,
// 4: 4/8]
#define LORA_PREAMBLE_LENGTH 8 // Same for Tx and Rx
#define LORA_SYMBOL_TIMEOUT 0 // Symbols
#define LORA_FIX_LENGTH_PAYLOAD_ON false
#define LORA_IQ_INVERSION_ON false

#define RX_TIMEOUT_VALUE 1000
#define BUFFER_SIZE 30 // Define the payload size here

char txpacket[BUFFER_SIZE];
char rxpacket[BUFFER_SIZE];

unsigned long time_now = 0;
unsigned long next_millis = 0;

static RadioEvents_t RadioEvents;

int16_t txnumber;

int16_t RSSI, rxSize;

void OnSleep()
{
  Serial.printf("into lowpower mode, %d ms later wake up.\r\n", timetowake);
  lowpower = true;
  //timetosleep ms later wake up;
  TimerSetValue( &wakeup, timetowake );
  TimerStart( &wakeup );
}
void OnWakeup()
{
  Serial.printf("wake up, %d ms later into lowpower mode.\r\n", timetosleep);
  lowpower = false;
  //timetosleep ms later into lowpower mode;
  TimerSetValue( &sleep, timetosleep );
  TimerStart( &sleep );
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  BoardInitMcu();
  Radio.Sleep( );

  pinMode(Vext, OUTPUT);
  digitalWrite(Vext, LOW);

  time_now = millis();
  while (millis() < time_now + 500) { // equivalent of delay(...);
  }

  Radio.Init( &RadioEvents );
  Radio.SetChannel( RF_FREQUENCY );
  Radio.SetTxConfig( MODEM_LORA, TX_OUTPUT_POWER, 0, LORA_BANDWIDTH,
                     LORA_SPREADING_FACTOR, LORA_CODINGRATE,
                     LORA_PREAMBLE_LENGTH, LORA_FIX_LENGTH_PAYLOAD_ON,
                     true, 0, 0, LORA_IQ_INVERSION_ON, 3000 );

  time_now = millis();
  while (millis() < time_now + 500) { // equivalent of delay(...);
  }

  TimerInit( &sleep, OnSleep );
  TimerInit( &wakeup, OnWakeup );
  OnSleep();
}

void loop() {

  // put your main code here, to run repeatedly:

  time_now = millis();
  while (millis() < time_now + 500) { // equivalent of delay(...);
  }

  char *str_temp;

  String msgT = "";

  msgT = "A test message.";

  memset(txpacket, 0, BUFFER_SIZE);

  // converting strig to a char?
  str_temp =  (char*)(msgT).c_str();

  sprintf(txpacket, "%s", str_temp);

  RGB_ON(COLOR_SEND, 0);

  Serial.printf("\r\nsending packet \"%s\" , length %d\r\n", txpacket, strlen(txpacket));

  Radio.Send( (uint8_t *)txpacket, strlen(txpacket) );

  RGB_ON(0, 0);

  time_now = millis();
  while (millis() < time_now + 500) { // equivalent of delay(...);
  }

  if (lowpower) {

    //note that LowPower_Handler() run six times the mcu into lowpower mode;
    LowPower_Handler();
  }

}
#2

Don’t use the LoRaWan_APP in P2P communication.

Here is a P2P example (PingPong communication):
https://github.com/HelTecAutomation/ASR650x-Arduino/blob/master/libraries/LoRa/examples/pingpong/pingpong.ino

And this is a low power example: