Example22_PowerOff.ino

/*
  Powering off a ublox GPS module
  By: bjorn
  unsurv.org
  Date: July 20th, 2020
  License: MIT. See license file for more information but you can
  basically do whatever you want with this code.

  This example shows you how to turn off the ublox module to lower the power consumption.
  There are two functions: one just specifies a duration in milliseconds the other also specifies a pin on the GPS device to wake it up with.
  By driving a voltage from LOW to HIGH or HIGH to LOW on the chosen module pin you wake the device back up.
  Note: Doing so on the INT0 pin when using the regular powerOff(durationInMs) function will wake the device anyway. (tested on SAM-M8Q)
  Note: While powered off, you should not query the device for data or it might wake up. This can be used to wake the device but is not recommended.
        Works best when also putting your microcontroller to sleep.

  Feel like supporting open source hardware?
  Buy a board from SparkFun!
  ZED-F9P RTK2: https://www.sparkfun.com/products/15136
  NEO-M8P RTK: https://www.sparkfun.com/products/15005
  SAM-M8Q: https://www.sparkfun.com/products/15106

  Hardware Connections:
  Plug a Qwiic cable into the GPS and a BlackBoard.
  To force the device to wake up you need to connect to a pin (for example INT0) seperately on the module.
  If you don't have a platform with a Qwiic connection use the SparkFun Qwiic Breadboard Jumper (https://www.sparkfun.com/products/14425)
  Open the serial monitor at 115200 baud to see the output
*/

#include "SparkFun_Ublox_Arduino_Library.h" //http://librarymanager/All#SparkFun_Ublox_GPS
SFE_UBLOX_GPS myGPS;

// define a digital pin capable of driving HIGH and LOW
#define WAKEUP_PIN 5

// Possible GNSS interrupt pins for powerOffWithInterrupt are:
// VAL_RXM_PMREQ_WAKEUPSOURCE_UARTRX  = uartrx
// VAL_RXM_PMREQ_WAKEUPSOURCE_EXTINT0 = extint0 (default)
// VAL_RXM_PMREQ_WAKEUPSOURCE_EXTINT1 = extint1
// VAL_RXM_PMREQ_WAKEUPSOURCE_SPICS   = spics
// These values can be or'd (|) together to enable interrupts on multiple pins

void wakeUp() {

  Serial.print("-- waking up module via pin " + String(WAKEUP_PIN));
  Serial.println(" on your microcontroller --");

  digitalWrite(WAKEUP_PIN, LOW);
  delay(1000);
  digitalWrite(WAKEUP_PIN, HIGH);
  delay(1000);
  digitalWrite(WAKEUP_PIN, LOW);
}


void setup() {

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

  Serial.begin(115200);
  while (!Serial); //Wait for user to open terminal
  Serial.println("SparkFun Ublox Example");

  Wire.begin();

  //myGPS.enableDebugging(); // Enable debug messages

  if (myGPS.begin() == false) //Connect to the Ublox module using Wire port
  {
    Serial.println(F("Ublox GPS not detected at default I2C address. Please check wiring. Freezing."));
    while (1);
  }

  // Powering off for 20s, you should see the power consumption drop.
  Serial.println("-- Powering off module for 20s --");

  myGPS.powerOff(20000);
  //myGPS.powerOffWithInterrupt(20000, VAL_RXM_PMREQ_WAKEUPSOURCE_EXTINT0);

  delay(10000);

  // After 10 seconds wake the device via the specified pin on your microcontroller and module.
  wakeUp();
}

void loop() {
  //Do nothing
}