Low power mode not working properly

[niranjan_187]

Hello all,

I recently started exploring the low power functionality of moteino, however, have been facing some issuse in making it work.

I tried the PIR motion sensor example mentioned here: https://codebender.cc/example/RFM69/MotionMote#MotionMote.ino and also I tried using the other libraries(narcoleptic and   Sleep_n0m1).   

I could make the LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF) command to work. But when I try to run radio.sleep() the moteino never wakes up after executing this command.

I also tried a few simple sketches to verify the same. And every time I add the radio.sleep() function the device never wakes up.

Is there some thing I am doing wrong or missing out? Below is the latest code I have been trying to make work.

Waiting for guidance and thank you in advance.

Code Select Expand

#include <RFM69.h>    //get it here: https://www.github.com/lowpowerlab/rfm69
#include <SPI.h>      //get it here: https://github.com/lowpowerlab/spiflash
#include <LowPower.h> //get library from: https://github.com/LowPowerLab/LowPower

#define NODEID        18    //unique for each node on same network
#define NETWORKID     100  //the same on all nodes that talk to each other
#define GATEWAYID     1
//Match frequency to the hardware version of the radio on your Moteino (uncomment one):
//#define FREQUENCY     RF69_433MHZ
#define FREQUENCY     RF69_868MHZ
//#define FREQUENCY     RF69_915MHZ
#define ENCRYPTKEY    "sampleEncryptKey" //exactly the same 16 characters/bytes on all nodes!
//#define IS_RFM69HW    //uncomment only for RFM69HW! Leave out if you have RFM69W!
#define ACK_TIME      30 // max # of ms to wait for an ack
#define LED           9  // Moteinos have LEDs on D9
#define SERIAL_BAUD   115200
#define MOTIONPIN     1 //hardware interrupt 1 (D3)

RFM69 radio;
volatile boolean motionDetected=false;

void setup() {
  Serial.begin(SERIAL_BAUD);
  radio.initialize(FREQUENCY,NODEID,NETWORKID);
#ifdef IS_RFM69HW
  radio.setHighPower(); //uncomment only for RFM69HW!
#endif
  radio.encrypt(ENCRYPTKEY);
  attachInterrupt(MOTIONPIN, motionIRQ, RISING);
  char buff[50];
  sprintf(buff, "\nTransmitting at %d Mhz...", FREQUENCY==RF69_433MHZ ? 433 : FREQUENCY==RF69_868MHZ ? 868 : 915);
  Serial.println(buff);
}

void motionIRQ()
{
  motionDetected=true;
}

void loop() {
 if (motionDetected)
  {
    if (radio.sendWithRetry(GATEWAYID, "MOTION", 6))
    {
     Serial.println(" ok!");
     Blink(LED,3);
    }
    else 
    {
      Serial.println(" nothing...");
    }
    
    motionDetected=false;
  }
  
  else 
  {
     Serial.println("waiting"); 
  }
//  radio.sleep();
  LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF);
  

}

void Blink(byte PIN, int DELAY_MS)
{
  pinMode(PIN, OUTPUT);
  digitalWrite(PIN,HIGH);
  delay(DELAY_MS);
  digitalWrite(PIN,LOW);
}

[TomWS]

Are you saying that if you leave the line "radio.sleep();" commented out, you get continuous serial output of "waiting" and if you uncomment, you get nothing?

If so, may I suggest that you add a line before uncommented radio.sleep() that has:

Code Select Expand

   Blink(100);
   radio.sleep();

And see if the LED blinks every 8 seconds?

Tom
Hint: It is highly recommended that you perform Serial.flush(); before and after sleeping...

[niranjan_187]

Hi Tom,

Thanks for a quick reply. Regarding the led blink, I tried as you mentioned and it is blinking.

However, I also tried the flush command and it seems to work now. Although I had the flush command before the low power commands. But as you suggested, I will add it after the low power commands as well and do a thorough testing and update you the same.

Thanks for the help. Get back to you soon.