├── .gitignore ├── .codespellrc ├── library.properties ├── .github ├── dependabot.yml └── workflows │ ├── spell-check.yml │ ├── check-arduino.yml │ ├── report-size-deltas.yml │ ├── compile-examples.yml │ └── sync-labels.yml ├── keywords.txt ├── docs ├── readme.md └── api.md ├── examples ├── TimedWakeup │ └── TimedWakeup.ino ├── ExternalWakeup │ └── ExternalWakeup.ino ├── TianStandby │ └── TianStandby.ino └── AdcWakeup │ └── AdcWakeup.ino ├── README.md ├── src ├── ArduinoLowPower.h └── samd │ └── ArduinoLowPower.cpp └── LICENSE /.gitignore: -------------------------------------------------------------------------------- 1 | .idea/ 2 | -------------------------------------------------------------------------------- /.codespellrc: -------------------------------------------------------------------------------- 1 | # See: https://github.com/codespell-project/codespell#using-a-config-file 2 | [codespell] 3 | # In the event of a false positive, add the problematic word, in all lowercase, to a comma-separated list here: 4 | ignore-words-list = , 5 | check-filenames = 6 | check-hidden = 7 | skip = ./.git 8 | -------------------------------------------------------------------------------- /library.properties: -------------------------------------------------------------------------------- 1 | name=Arduino Low Power 2 | version=1.2.2 3 | author=Arduino 4 | maintainer=Arduino 5 | sentence=Power save primitives features for SAMD and nRF52 32bit boards 6 | paragraph=With this library you can manage the low power states of newer Arduino boards 7 | category=Device Control 8 | url=https://www.arduino.cc/libraries/ArduinoLowPower 9 | architectures=samd 10 | depends=RTCZero 11 | -------------------------------------------------------------------------------- /.github/dependabot.yml: -------------------------------------------------------------------------------- 1 | # See: https://docs.github.com/en/github/administering-a-repository/configuration-options-for-dependency-updates#about-the-dependabotyml-file 2 | version: 2 3 | 4 | updates: 5 | # Configure check for outdated GitHub Actions actions in workflows. 6 | # See: https://docs.github.com/en/github/administering-a-repository/keeping-your-actions-up-to-date-with-dependabot 7 | - package-ecosystem: github-actions 8 | directory: / # Check the repository's workflows under /.github/workflows/ 9 | schedule: 10 | interval: daily 11 | labels: 12 | - "topic: infrastructure" 13 | -------------------------------------------------------------------------------- /.github/workflows/spell-check.yml: -------------------------------------------------------------------------------- 1 | name: Spell Check 2 | 3 | # See: https://docs.github.com/en/free-pro-team@latest/actions/reference/events-that-trigger-workflows 4 | on: 5 | push: 6 | pull_request: 7 | schedule: 8 | # Run every Tuesday at 8 AM UTC to catch new misspelling detections resulting from dictionary updates. 9 | - cron: "0 8 * * TUE" 10 | workflow_dispatch: 11 | repository_dispatch: 12 | 13 | jobs: 14 | spellcheck: 15 | runs-on: ubuntu-latest 16 | 17 | steps: 18 | - name: Checkout repository 19 | uses: actions/checkout@v6 20 | 21 | - name: Spell check 22 | uses: codespell-project/actions-codespell@master 23 | -------------------------------------------------------------------------------- /.github/workflows/check-arduino.yml: -------------------------------------------------------------------------------- 1 | name: Check Arduino 2 | 3 | # See: https://docs.github.com/en/free-pro-team@latest/actions/reference/events-that-trigger-workflows 4 | on: 5 | push: 6 | pull_request: 7 | schedule: 8 | # Run every Tuesday at 8 AM UTC to catch breakage caused by new rules added to Arduino Lint. 9 | - cron: "0 8 * * TUE" 10 | workflow_dispatch: 11 | repository_dispatch: 12 | 13 | jobs: 14 | lint: 15 | runs-on: ubuntu-latest 16 | 17 | steps: 18 | - name: Checkout repository 19 | uses: actions/checkout@v6 20 | 21 | - name: Arduino Lint 22 | uses: arduino/arduino-lint-action@v2 23 | with: 24 | compliance: specification 25 | library-manager: update 26 | # Always use this setting for official repositories. Remove for 3rd party projects. 27 | official: true 28 | project-type: library 29 | -------------------------------------------------------------------------------- /keywords.txt: -------------------------------------------------------------------------------- 1 | ####################################### 2 | # Syntax Coloring Map For Arduino Low Power 3 | ####################################### 4 | 5 | ####################################### 6 | # Datatypes (KEYWORD1) 7 | ####################################### 8 | 9 | ArduinoLowPower KEYWORD1 10 | LowPower KEYWORD1 11 | 12 | ####################################### 13 | # Methods and Functions (KEYWORD2) 14 | ####################################### 15 | 16 | idle KEYWORD2 17 | sleep KEYWORD2 18 | deepSleep KEYWORD2 19 | attachInterruptWakeup KEYWORD2 20 | enableWakeupFrom KEYWORD2 21 | companionLowPowerCallback KEYWORD2 22 | companionSleep KEYWORD2 23 | companionWakeup KEYWORD2 24 | wakeupReason KEYWORD2 25 | 26 | ####################################### 27 | # Constants (LITERAL1) 28 | ####################################### 29 | 30 | OTHER_WAKEUP LITERAL1 31 | GPIO_WAKEUP LITERAL1 32 | NFC_WAKEUP LITERAL1 33 | ANALOG_COMPARATOR_WAKEUP LITERAL1 34 | -------------------------------------------------------------------------------- /.github/workflows/report-size-deltas.yml: -------------------------------------------------------------------------------- 1 | name: Report Size Deltas 2 | 3 | # See: https://docs.github.com/en/free-pro-team@latest/actions/reference/events-that-trigger-workflows 4 | on: 5 | push: 6 | paths: 7 | - ".github/workflows/report-size-deltas.yml" 8 | schedule: 9 | # Run at the minimum interval allowed by GitHub Actions. 10 | # Note: GitHub Actions periodically has outages which result in workflow failures. 11 | # In this event, the workflows will start passing again once the service recovers. 12 | - cron: "*/5 * * * *" 13 | workflow_dispatch: 14 | repository_dispatch: 15 | 16 | jobs: 17 | report: 18 | runs-on: ubuntu-latest 19 | steps: 20 | - name: Comment size deltas reports to PRs 21 | uses: arduino/report-size-deltas@v1 22 | with: 23 | # Regex matching the names of the workflow artifacts created by the "Compile Examples" workflow 24 | sketches-reports-source: ^sketches-report-.+ 25 | -------------------------------------------------------------------------------- /docs/readme.md: -------------------------------------------------------------------------------- 1 | # Arduino Low Power Library 2 | 3 | This library allows you to use the low power features of the SAMD21 MCU, which is used for all [MKR family boards](https://store.arduino.cc/collections/mkr-family) and the [Nano 33 IoT board](https://store.arduino.cc/products/arduino-nano-33-iot). 4 | 5 | In these pages, the term companion chip is used. This term refers to a board co-processor like the MIPS processor on the [Arduino Tian](https://docs.arduino.cc/retired/boards/arduino-tian). 6 | 7 | To use this library: 8 | 9 | ``` 10 | #include "" 11 | ``` 12 | 13 | Examples: 14 | 15 | - [ExternalWakeup](https://github.com/arduino-libraries/ArduinoLowPower/blob/master/examples/ExternalWakeup/ExternalWakeup.ino) : Demonstrates how to wake your board from an external source like a button. 16 | - [TianStandby](https://github.com/arduino-libraries/ArduinoLowPower/blob/master/examples/TianStandby/TianStandby.ino) : Demonstrates how to put a Tian in standby 17 | - [TimedWakeup](https://github.com/arduino-libraries/ArduinoLowPower/blob/master/examples/TimedWakeup/TimedWakeup.ino) : Demonstrates how to put in sleep your board for a certain amount of time -------------------------------------------------------------------------------- /examples/TimedWakeup/TimedWakeup.ino: -------------------------------------------------------------------------------- 1 | /* 2 | TimedWakeup 3 | 4 | This sketch demonstrates the usage of Internal Interrupts to wakeup a chip in sleep mode. 5 | Sleep modes allow a significant drop in the power usage of a board while it does nothing waiting for an event to happen. Battery powered application can take advantage of these modes to enhance battery life significantly. 6 | 7 | In this sketch, the internal RTC will wake up the processor every 2 seconds. 8 | Please note that, if the processor is sleeping, a new sketch can't be uploaded. To overcome this, manually reset the board (usually with a single or double tap to the RESET button) 9 | 10 | This example code is in the public domain. 11 | */ 12 | 13 | #include "ArduinoLowPower.h" 14 | 15 | void setup() { 16 | pinMode(LED_BUILTIN, OUTPUT); 17 | // Uncomment this function if you wish to attach function dummy when RTC wakes up the chip 18 | // LowPower.attachInterruptWakeup(RTC_ALARM_WAKEUP, dummy, CHANGE); 19 | } 20 | 21 | void loop() { 22 | digitalWrite(LED_BUILTIN, HIGH); 23 | delay(500); 24 | digitalWrite(LED_BUILTIN, LOW); 25 | delay(500); 26 | // Triggers a 2000 ms sleep (the device will be woken up only by the registered wakeup sources and by internal RTC) 27 | // The power consumption of the chip will drop consistently 28 | LowPower.sleep(2000); 29 | } 30 | 31 | void dummy() { 32 | // This function will be called once on device wakeup 33 | // You can do some little operations here (like changing variables which will be used in the loop) 34 | // Remember to avoid calling delay() and long running functions since this functions executes in interrupt context 35 | } -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Arduino Low Power library 2 | 3 | [![Check Arduino status](https://github.com/arduino-libraries/ArduinoLowPower/actions/workflows/check-arduino.yml/badge.svg)](https://github.com/arduino-libraries/ArduinoLowPower/actions/workflows/check-arduino.yml) 4 | [![Compile Examples status](https://github.com/arduino-libraries/ArduinoLowPower/actions/workflows/compile-examples.yml/badge.svg)](https://github.com/arduino-libraries/ArduinoLowPower/actions/workflows/compile-examples.yml) 5 | [![Spell Check status](https://github.com/arduino-libraries/ArduinoLowPower/actions/workflows/spell-check.yml/badge.svg)](https://github.com/arduino-libraries/ArduinoLowPower/actions/workflows/spell-check.yml) 6 | 7 | This library allows the use of the low power features of the SAMD21 MCU. This means your battery powered projects will have a longer battery life on boards like [MKRZero](https://store.arduino.cc/usa/arduino-mkrzero), [MKR1000](https://www.arduino.cc/en/Main/ArduinoMKR1000) and [MKRFox1200](https://www.arduino.cc/en/Main/ArduinoBoardMKRFox1200). 8 | 9 | For more information about this library please visit us at 10 | 11 | 12 | # License 13 | Copyright (c) Arduino LLC. All right reserved. 14 | 15 | This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. 16 | 17 | This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. 18 | 19 | You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 20 | -------------------------------------------------------------------------------- /examples/ExternalWakeup/ExternalWakeup.ino: -------------------------------------------------------------------------------- 1 | /* 2 | ExternalWakeup 3 | 4 | This sketch demonstrates the usage of External Interrupts (on pins) to wakeup a chip in sleep mode. 5 | Sleep modes allow a significant drop in the power usage of a board while it does nothing waiting for an event to happen. Battery powered application can take advantage of these modes to enhance battery life significantly. 6 | 7 | In this sketch, shorting pin 8 to a GND will wake up the board. 8 | Please note that, if the processor is sleeping, a new sketch can't be uploaded. To overcome this, manually reset the board (usually with a single or double tap to the RESET button) 9 | 10 | This example code is in the public domain. 11 | */ 12 | 13 | #include "ArduinoLowPower.h" 14 | 15 | // Blink sequence number 16 | // Declare it volatile since it's incremented inside an interrupt 17 | volatile int repetitions = 1; 18 | 19 | // Pin used to trigger a wakeup 20 | const int pin = 8; 21 | 22 | void setup() { 23 | pinMode(LED_BUILTIN, OUTPUT); 24 | // Set pin 8 as INPUT_PULLUP to avoid spurious wakeup 25 | pinMode(pin, INPUT_PULLUP); 26 | // Attach a wakeup interrupt on pin 8, calling repetitionsIncrease when the device is woken up 27 | LowPower.attachInterruptWakeup(pin, repetitionsIncrease, CHANGE); 28 | } 29 | 30 | void loop() { 31 | for (int i = 0; i < repetitions; i++) { 32 | digitalWrite(LED_BUILTIN, HIGH); 33 | delay(500); 34 | digitalWrite(LED_BUILTIN, LOW); 35 | delay(500); 36 | } 37 | // Triggers an infinite sleep (the device will be woken up only by the registered wakeup sources) 38 | // The power consumption of the chip will drop consistently 39 | LowPower.sleep(); 40 | } 41 | 42 | void repetitionsIncrease() { 43 | // This function will be called once on device wakeup 44 | // You can do some little operations here (like changing variables which will be used in the loop) 45 | // Remember to avoid calling delay() and long running functions since this functions executes in interrupt context 46 | repetitions ++; 47 | } -------------------------------------------------------------------------------- /examples/TianStandby/TianStandby.ino: -------------------------------------------------------------------------------- 1 | /* 2 | TianStandby 3 | 4 | This sketch demonstrates the usage of SAMD chip to further reduce the power usage of the Tian 5 | board. This method can be applied to any board with companion chips which expose a method 6 | (via direct pin interrupt or via a command) to enter and exit standby. 7 | Sleep modes allow a significant drop in the power usage of a board while it does nothing waiting for an event to happen. Battery powered applications can take advantage of these modes to enhance battery life significantly. 8 | 9 | In this sketch, the internal RTC of the SAMD chip will wake up the processor every 20 seconds. 10 | Before going to sleep, the SAMD chip tells the MIPS CPU to standby too. 11 | Please note that, if the processor is sleeping, a new sketch can't be uploaded. To overcome this, manually reset the board (usually with a single or double tap to the RESET button) 12 | 13 | This example code is in the public domain. 14 | */ 15 | 16 | #include "ArduinoLowPower.h" 17 | 18 | #define MIPS_PIN 32 19 | 20 | void MipsPM(bool sleep) { 21 | pinMode(MIPS_PIN, OUTPUT); 22 | digitalWrite(MIPS_PIN, sleep ? LOW: HIGH); 23 | } 24 | 25 | void setup() { 26 | pinMode(LED_BUILTIN, OUTPUT); 27 | LowPower.companionLowPowerCallback(MipsPM); 28 | // Uncomment this function if you wish to attach function dummy when RTC wakes up the chip 29 | LowPower.attachInterruptWakeup(RTC_ALARM_WAKEUP, onWakeup, CHANGE); 30 | } 31 | 32 | void loop() { 33 | digitalWrite(LED_BUILTIN, HIGH); 34 | delay(500); 35 | digitalWrite(LED_BUILTIN, LOW); 36 | delay(500); 37 | // Triggers a 2000 ms sleep (the device will be woken up only by the registered wakeup sources and by internal RTC) 38 | // The power consumption of the chip will drop consistently 39 | // Send sleep command to MIPS CPU and then go to sleep 40 | LowPower.companionSleep(); 41 | LowPower.sleep(20000); 42 | } 43 | 44 | void onWakeup() { 45 | // This function will be called once on device wakeup 46 | // You can do some little operations here (like changing variables which will be used in the loop) 47 | // Remember to avoid calling delay() and long running functions since this functions executes in interrupt context 48 | 49 | // Wakeup the companion chip, too 50 | LowPower.companionWakeup(); 51 | } 52 | -------------------------------------------------------------------------------- /examples/AdcWakeup/AdcWakeup.ino: -------------------------------------------------------------------------------- 1 | /* 2 | AdcWakeup 3 | 4 | This sketch demonstrates the usage of the ADC to wakeup a chip in sleep mode. 5 | Sleep modes allow a significant drop in the power usage of a board while it does nothing waiting for an event to happen. Battery powered application can take advantage of these modes to enhance battery life significantly. 6 | 7 | In this sketch, changing the voltage on pin A0 will wake up the board. You can test this by connecting a potentiometer between VCC, A0, and GND. 8 | Please note that, if the processor is sleeping, a new sketch can't be uploaded. To overcome this, manually reset the board (usually with a single or double tap to the RESET button) 9 | 10 | This example code is in the public domain. 11 | */ 12 | 13 | #include "ArduinoLowPower.h" 14 | 15 | // Blink sequence number 16 | // Declare it volatile since it's incremented inside an interrupt 17 | volatile int repetitions = 1; 18 | 19 | // Pin used to trigger a wakeup 20 | const int pin = A0; 21 | // How sensitive to be to changes in voltage 22 | const int margin = 10; 23 | 24 | void setup() { 25 | pinMode(LED_BUILTIN, OUTPUT); 26 | pinMode(pin, INPUT); 27 | } 28 | 29 | void loop() { 30 | for (int i = 0; i < repetitions; i++) { 31 | digitalWrite(LED_BUILTIN, HIGH); 32 | delay(500); 33 | digitalWrite(LED_BUILTIN, LOW); 34 | delay(500); 35 | } 36 | 37 | // Read the voltage at the ADC pin 38 | int value = analogRead(pin); 39 | 40 | // Define a window around that value 41 | uint16_t lo = max(value - margin, 0); 42 | uint16_t hi = min(value + margin, UINT16_MAX); 43 | 44 | // Attach an ADC interrupt on pin A0, calling repetitionsIncrease when the voltage is outside the given range. 45 | // This should be called immediately before LowPower.sleep() because it reconfigures the ADC internally. 46 | LowPower.attachAdcInterrupt(pin, repetitionsIncrease, ADC_INT_OUTSIDE, lo, hi); 47 | 48 | // Triggers an infinite sleep (the device will be woken up only by the registered wakeup sources) 49 | // The power consumption of the chip will drop consistently 50 | LowPower.sleep(); 51 | 52 | // Detach the ADC interrupt. This should be called immediately after LowPower.sleep() because it restores the ADC configuration after waking up. 53 | LowPower.detachAdcInterrupt(); 54 | } 55 | 56 | void repetitionsIncrease() { 57 | // This function will be called once on device wakeup 58 | // You can do some little operations here (like changing variables which will be used in the loop) 59 | // Remember to avoid calling delay() and long running functions since this functions executes in interrupt context 60 | repetitions ++; 61 | } -------------------------------------------------------------------------------- /src/ArduinoLowPower.h: -------------------------------------------------------------------------------- 1 | #ifndef _ARDUINO_LOW_POWER_H_ 2 | #define _ARDUINO_LOW_POWER_H_ 3 | 4 | #include 5 | 6 | #ifdef ARDUINO_ARCH_AVR 7 | #error The library is not compatible with AVR boards 8 | #endif 9 | 10 | #ifdef ARDUINO_ARCH_SAMD 11 | #include "RTCZero.h" 12 | #endif 13 | 14 | #if defined(ARDUINO_SAMD_TIAN) || defined(ARDUINO_NRF52_PRIMO) 15 | // add here any board with companion chip which can be woken up 16 | #define BOARD_HAS_COMPANION_CHIP 17 | #endif 18 | 19 | #define RTC_ALARM_WAKEUP 0xFF 20 | 21 | #ifdef ARDUINO_API_VERSION 22 | using irq_mode = PinStatus; 23 | #else 24 | using irq_mode = uint32_t; 25 | #endif 26 | 27 | //typedef void (*voidFuncPtr)( void ) ; 28 | typedef void (*onOffFuncPtr)( bool ) ; 29 | 30 | typedef enum{ 31 | OTHER_WAKEUP = 0, 32 | GPIO_WAKEUP = 1, 33 | NFC_WAKEUP = 2, 34 | ANALOG_COMPARATOR_WAKEUP = 3 35 | } wakeup_reason; 36 | 37 | #ifdef ARDUINO_ARCH_SAMD 38 | enum adc_interrupt 39 | { 40 | ADC_INT_BETWEEN, 41 | ADC_INT_OUTSIDE, 42 | ADC_INT_ABOVE_MIN, 43 | ADC_INT_BELOW_MAX, 44 | }; 45 | #endif 46 | 47 | 48 | class ArduinoLowPowerClass { 49 | public: 50 | void idle(void); 51 | void idle(uint32_t millis); 52 | void idle(int millis) { 53 | idle((uint32_t)millis); 54 | } 55 | 56 | void sleep(void); 57 | void sleep(uint32_t millis); 58 | void sleep(int millis) { 59 | sleep((uint32_t)millis); 60 | } 61 | 62 | void deepSleep(void); 63 | void deepSleep(uint32_t millis); 64 | void deepSleep(int millis) { 65 | deepSleep((uint32_t)millis); 66 | } 67 | 68 | void attachInterruptWakeup(uint32_t pin, voidFuncPtr callback, irq_mode mode); 69 | 70 | #ifdef BOARD_HAS_COMPANION_CHIP 71 | void companionLowPowerCallback(onOffFuncPtr callback) { 72 | companionSleepCB = callback; 73 | } 74 | void companionSleep() { 75 | companionSleepCB(true); 76 | } 77 | void companionWakeup() { 78 | companionSleepCB(false); 79 | } 80 | #endif 81 | 82 | #ifdef ARDUINO_ARCH_NRF52 83 | void enableWakeupFrom(wakeup_reason peripheral, uint32_t pin = 0xFF, uint32_t event = 0xFF, uint32_t option = 0xFF); 84 | wakeup_reason wakeupReason(); 85 | #endif 86 | 87 | #ifdef ARDUINO_ARCH_SAMD 88 | void attachAdcInterrupt(uint32_t pin, voidFuncPtr callback, adc_interrupt mode, uint16_t lo, uint16_t hi); 89 | void detachAdcInterrupt(); 90 | #endif 91 | 92 | private: 93 | void setAlarmIn(uint32_t millis); 94 | #ifdef ARDUINO_ARCH_SAMD 95 | RTCZero rtc; 96 | voidFuncPtr adc_cb; 97 | friend void ADC_Handler(); 98 | #endif 99 | #ifdef BOARD_HAS_COMPANION_CHIP 100 | void (*companionSleepCB)(bool); 101 | #endif 102 | }; 103 | 104 | extern ArduinoLowPowerClass LowPower; 105 | 106 | #endif 107 | -------------------------------------------------------------------------------- /docs/api.md: -------------------------------------------------------------------------------- 1 | # Ardunio Low Power 2 | 3 | ## Methods 4 | 5 | ### `LowPower.idle()` 6 | 7 | #### Description 8 | 9 | Puts the MCU in IDLE mode. This mode allows power optimization with the fastest wake-up time. The CPU is stopped. To further reduce power consumption, the user can manually disable the clocking of modules and clock sources. 10 | 11 | 12 | #### Syntax 13 | 14 | ``` 15 | LowPower.idle(); 16 | LowPower.idle(milliseconds); 17 | ``` 18 | 19 | #### Parameters 20 | 21 | milliseconds: the number of milliseconds to put the board in idle mode. If void the idle mode is used till a wakeup event. 22 | 23 | ### `LowPower.sleep()` 24 | 25 | #### Description 26 | 27 | Puts the MCU in sleep mode. The sleep mode allows power optimization with a slower wakeup time. Only the chosen peripherals are on. 28 | 29 | 30 | #### Syntax 31 | 32 | ``` 33 | LowPower.sleep(); 34 | LowPower.sleep(milliseconds); 35 | ``` 36 | 37 | #### Parameters 38 | 39 | milliseconds: the number of milliseconds to put the board in sleep mode. If void the sleep mode is used till a wakeup event. 40 | 41 | ### `LowPower.deepSleep()` 42 | 43 | #### Description 44 | 45 | Puts the MCU in deep sleep mode. The deep sleep mode allows power optimization with the slowest wake-up time. All but the RTC peripherals are stopped. The CPU can be wakeup only using RTC or wakeup on interrupt capable pins. 46 | 47 | 48 | #### Syntax 49 | 50 | ``` 51 | LowPower.deepSleep(); 52 | LowPower.deepSleep(milliseconds); 53 | ``` 54 | 55 | #### Parameters 56 | 57 | milliseconds: the number of milliseconds to put the board in deep sleep mode. If void the deep sleep mode is used till a wakeup event. 58 | 59 | ### `LowPower.attachInterruptWakeup()` 60 | 61 | #### Description 62 | 63 | Indicates the function to call and the conditions for a wakeup event. 64 | 65 | 66 | #### Syntax 67 | 68 | ``` 69 | LowPower.attachInterruptWakeup(pin, callback, mode); 70 | ``` 71 | 72 | #### Parameters 73 | 74 | pin: the pin used as external wakeup 75 | 76 | callback: the function to call on wakeup 77 | 78 | mode: the transitions to sense on the indicated pin. Can be one between: 79 | 80 | - FALLING 81 | - RISING 82 | - CHANGE 83 | 84 | ### `LowPower.CompanionLowPowerCallback()` 85 | 86 | #### Description 87 | 88 | Indicates the function that the on-boad co-processor (Tian only) has to call just before going to sleep. 89 | 90 | 91 | #### Syntax 92 | 93 | LowPower.CompanionLowPowerCallback(callback); 94 | 95 | #### Parameters 96 | 97 | callback: the function to call before going to sleep 98 | 99 | ### `LowPower.companionSleep()` 100 | 101 | #### Description 102 | 103 | Puts the on-board co-processor (Tian only) in sleep mode 104 | 105 | 106 | #### Syntax 107 | 108 | LowPower.companionSleep(); 109 | 110 | #### Parameters 111 | 112 | None 113 | 114 | ### `LowPower.companionWakeup()` 115 | 116 | #### Description 117 | 118 | Forces the on board co-processor (Tian only) wakeup from sleep mode. 119 | 120 | 121 | #### Syntax 122 | 123 | ``` 124 | LowPower.companionWakeup(); 125 | ``` 126 | 127 | #### Parameters 128 | 129 | None -------------------------------------------------------------------------------- /.github/workflows/compile-examples.yml: -------------------------------------------------------------------------------- 1 | name: Compile Examples 2 | 3 | # See: https://docs.github.com/en/free-pro-team@latest/actions/reference/events-that-trigger-workflows 4 | on: 5 | push: 6 | paths: 7 | - ".github/workflows/compile-examples.yml" 8 | - "examples/**" 9 | - "src/**" 10 | pull_request: 11 | paths: 12 | - ".github/workflows/compile-examples.yml" 13 | - "examples/**" 14 | - "src/**" 15 | schedule: 16 | # Run every Tuesday at 8 AM UTC to catch breakage caused by changes to external resources (libraries, platforms). 17 | - cron: "0 8 * * TUE" 18 | workflow_dispatch: 19 | repository_dispatch: 20 | 21 | jobs: 22 | build: 23 | name: ${{ matrix.board.fqbn }} 24 | runs-on: ubuntu-latest 25 | 26 | env: 27 | SKETCHES_REPORTS_PATH: sketches-reports 28 | 29 | strategy: 30 | fail-fast: false 31 | 32 | matrix: 33 | board: 34 | - fqbn: arduino:samd:arduino_zero_edbg 35 | platforms: | 36 | - name: arduino:samd 37 | artifact-name-suffix: arduino-samd-arduino_zero_edbg 38 | - fqbn: arduino:samd:mkr1000 39 | platforms: | 40 | - name: arduino:samd 41 | artifact-name-suffix: arduino-samd-mkr1000 42 | - fqbn: arduino:samd:mkrzero 43 | platforms: | 44 | - name: arduino:samd 45 | artifact-name-suffix: arduino-samd-mkrzero 46 | - fqbn: arduino:samd:mkrwifi1010 47 | platforms: | 48 | - name: arduino:samd 49 | artifact-name-suffix: arduino-samd-mkrwifi1010 50 | - fqbn: arduino:samd:mkrfox1200 51 | platforms: | 52 | - name: arduino:samd 53 | artifact-name-suffix: arduino-samd-mkrfox1200 54 | - fqbn: arduino:samd:mkrwan1300 55 | platforms: | 56 | - name: arduino:samd 57 | artifact-name-suffix: arduino-samd-mkrwan1300 58 | - fqbn: arduino:samd:mkrwan1310 59 | platforms: | 60 | - name: arduino:samd 61 | artifact-name-suffix: arduino-samd-mkrwan1310 62 | - fqbn: arduino:samd:mkrgsm1400 63 | platforms: | 64 | - name: arduino:samd 65 | artifact-name-suffix: arduino-samd-mkrgsm1400 66 | - fqbn: arduino:samd:mkrnb1500 67 | platforms: | 68 | - name: arduino:samd 69 | artifact-name-suffix: arduino-samd-mkrnb1500 70 | - fqbn: arduino:samd:mkrvidor4000 71 | platforms: | 72 | - name: arduino:samd 73 | artifact-name-suffix: arduino-samd-mkrvidor4000 74 | - fqbn: arduino:samd:nano_33_iot 75 | platforms: | 76 | - name: arduino:samd 77 | artifact-name-suffix: arduino-samd-nano_33_iot 78 | - fqbn: arduino:samd:tian 79 | platforms: | 80 | - name: arduino:samd 81 | artifact-name-suffix: arduino-samd-tian 82 | sketch-paths: | 83 | - examples/TianStandby 84 | 85 | steps: 86 | - name: Checkout repository 87 | uses: actions/checkout@v6 88 | 89 | - name: Compile examples 90 | uses: arduino/compile-sketches@v1 91 | with: 92 | github-token: ${{ secrets.GITHUB_TOKEN }} 93 | fqbn: ${{ matrix.board.fqbn }} 94 | platforms: ${{ matrix.board.platforms }} 95 | libraries: | 96 | # Install the library from the local path. 97 | - source-path: ./ 98 | - name: RTCZero 99 | sketch-paths: | 100 | # Sketches to compile for all boards 101 | - examples/AdcWakeup 102 | - examples/ExternalWakeup 103 | - examples/TimedWakeup 104 | # Board-specific sketches 105 | ${{ matrix.board.sketch-paths }} 106 | enable-deltas-report: true 107 | sketches-report-path: ${{ env.SKETCHES_REPORTS_PATH }} 108 | 109 | - name: Save sketches report as workflow artifact 110 | uses: actions/upload-artifact@v6 111 | with: 112 | if-no-files-found: error 113 | path: ${{ env.SKETCHES_REPORTS_PATH }} 114 | name: sketches-report-${{ matrix.board.artifact-name-suffix }} 115 | -------------------------------------------------------------------------------- /.github/workflows/sync-labels.yml: -------------------------------------------------------------------------------- 1 | # Source: https://github.com/arduino/tooling-project-assets/blob/main/workflow-templates/sync-labels.md 2 | name: Sync Labels 3 | 4 | # See: https://docs.github.com/en/actions/reference/events-that-trigger-workflows 5 | on: 6 | push: 7 | paths: 8 | - ".github/workflows/sync-labels.ya?ml" 9 | - ".github/label-configuration-files/*.ya?ml" 10 | pull_request: 11 | paths: 12 | - ".github/workflows/sync-labels.ya?ml" 13 | - ".github/label-configuration-files/*.ya?ml" 14 | schedule: 15 | # Run daily at 8 AM UTC to sync with changes to shared label configurations. 16 | - cron: "0 8 * * *" 17 | workflow_dispatch: 18 | repository_dispatch: 19 | 20 | env: 21 | CONFIGURATIONS_FOLDER: .github/label-configuration-files 22 | CONFIGURATIONS_ARTIFACT: label-configuration-files 23 | 24 | jobs: 25 | check: 26 | runs-on: ubuntu-latest 27 | 28 | steps: 29 | - name: Checkout repository 30 | uses: actions/checkout@v6 31 | 32 | - name: Download JSON schema for labels configuration file 33 | id: download-schema 34 | uses: carlosperate/download-file-action@v2 35 | with: 36 | file-url: https://raw.githubusercontent.com/arduino/tooling-project-assets/main/workflow-templates/assets/sync-labels/arduino-tooling-gh-label-configuration-schema.json 37 | location: ${{ runner.temp }}/label-configuration-schema 38 | 39 | - name: Install JSON schema validator 40 | run: | 41 | sudo npm install \ 42 | --global \ 43 | ajv-cli \ 44 | ajv-formats 45 | 46 | - name: Validate local labels configuration 47 | run: | 48 | # See: https://github.com/ajv-validator/ajv-cli#readme 49 | ajv validate \ 50 | --all-errors \ 51 | -c ajv-formats \ 52 | -s "${{ steps.download-schema.outputs.file-path }}" \ 53 | -d "${{ env.CONFIGURATIONS_FOLDER }}/*.{yml,yaml}" 54 | 55 | download: 56 | needs: check 57 | runs-on: ubuntu-latest 58 | 59 | strategy: 60 | matrix: 61 | filename: 62 | # Filenames of the shared configurations to apply to the repository in addition to the local configuration. 63 | # https://github.com/arduino/tooling-project-assets/blob/main/workflow-templates/assets/sync-labels 64 | - universal.yml 65 | 66 | steps: 67 | - name: Download 68 | uses: carlosperate/download-file-action@v2 69 | with: 70 | file-url: https://raw.githubusercontent.com/arduino/tooling-project-assets/main/workflow-templates/assets/sync-labels/${{ matrix.filename }} 71 | 72 | - name: Pass configuration files to next job via workflow artifact 73 | uses: actions/upload-artifact@v6 74 | with: 75 | path: | 76 | *.yaml 77 | *.yml 78 | if-no-files-found: error 79 | name: ${{ env.CONFIGURATIONS_ARTIFACT }} 80 | 81 | sync: 82 | needs: download 83 | runs-on: ubuntu-latest 84 | 85 | steps: 86 | - name: Set environment variables 87 | run: | 88 | # See: https://docs.github.com/en/actions/reference/workflow-commands-for-github-actions#setting-an-environment-variable 89 | echo "MERGED_CONFIGURATION_PATH=${{ runner.temp }}/labels.yml" >> "$GITHUB_ENV" 90 | 91 | - name: Determine whether to dry run 92 | id: dry-run 93 | if: > 94 | github.event_name == 'pull_request' || 95 | ( 96 | ( 97 | github.event_name == 'push' || 98 | github.event_name == 'workflow_dispatch' 99 | ) && 100 | github.ref != format('refs/heads/{0}', github.event.repository.default_branch) 101 | ) 102 | run: | 103 | # Use of this flag in the github-label-sync command will cause it to only check the validity of the 104 | # configuration. 105 | echo "::set-output name=flag::--dry-run" 106 | 107 | - name: Checkout repository 108 | uses: actions/checkout@v6 109 | 110 | - name: Download configuration files artifact 111 | uses: actions/download-artifact@v7 112 | with: 113 | name: ${{ env.CONFIGURATIONS_ARTIFACT }} 114 | path: ${{ env.CONFIGURATIONS_FOLDER }} 115 | 116 | - name: Remove unneeded artifact 117 | uses: geekyeggo/delete-artifact@v5 118 | with: 119 | name: ${{ env.CONFIGURATIONS_ARTIFACT }} 120 | 121 | - name: Merge label configuration files 122 | run: | 123 | # Merge all configuration files 124 | shopt -s extglob 125 | cat "${{ env.CONFIGURATIONS_FOLDER }}"/*.@(yml|yaml) > "${{ env.MERGED_CONFIGURATION_PATH }}" 126 | 127 | - name: Install github-label-sync 128 | run: sudo npm install --global github-label-sync 129 | 130 | - name: Sync labels 131 | env: 132 | GITHUB_ACCESS_TOKEN: ${{ secrets.GITHUB_TOKEN }} 133 | run: | 134 | # See: https://github.com/Financial-Times/github-label-sync 135 | github-label-sync \ 136 | --labels "${{ env.MERGED_CONFIGURATION_PATH }}" \ 137 | ${{ steps.dry-run.outputs.flag }} \ 138 | ${{ github.repository }} 139 | -------------------------------------------------------------------------------- /src/samd/ArduinoLowPower.cpp: -------------------------------------------------------------------------------- 1 | #if defined(ARDUINO_ARCH_SAMD) 2 | 3 | #include "ArduinoLowPower.h" 4 | 5 | static void configGCLK6() 6 | { 7 | // enable EIC clock 8 | GCLK->CLKCTRL.bit.CLKEN = 0; //disable GCLK module 9 | while (GCLK->STATUS.bit.SYNCBUSY); 10 | 11 | GCLK->CLKCTRL.reg = (uint16_t) (GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK6 | GCLK_CLKCTRL_ID( GCM_EIC )) ; //EIC clock switched on GCLK6 12 | while (GCLK->STATUS.bit.SYNCBUSY); 13 | 14 | GCLK->GENCTRL.reg = (GCLK_GENCTRL_GENEN | GCLK_GENCTRL_SRC_OSCULP32K | GCLK_GENCTRL_ID(6)); //source for GCLK6 is OSCULP32K 15 | while (GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY); 16 | 17 | GCLK->GENCTRL.bit.RUNSTDBY = 1; //GCLK6 run standby 18 | while (GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY); 19 | 20 | /* Errata: Make sure that the Flash does not power all the way down 21 | * when in sleep mode. */ 22 | 23 | NVMCTRL->CTRLB.bit.SLEEPPRM = NVMCTRL_CTRLB_SLEEPPRM_DISABLED_Val; 24 | } 25 | 26 | void ArduinoLowPowerClass::idle() { 27 | SCB->SCR &= ~SCB_SCR_SLEEPDEEP_Msk; 28 | PM->SLEEP.reg = 2; 29 | __DSB(); 30 | __WFI(); 31 | } 32 | 33 | void ArduinoLowPowerClass::idle(uint32_t millis) { 34 | setAlarmIn(millis); 35 | idle(); 36 | } 37 | 38 | void ArduinoLowPowerClass::sleep() { 39 | bool restoreUSBDevice = false; 40 | if (SERIAL_PORT_USBVIRTUAL) { 41 | USBDevice.standby(); 42 | } else { 43 | USBDevice.detach(); 44 | restoreUSBDevice = true; 45 | } 46 | // Disable systick interrupt: See https://www.avrfreaks.net/forum/samd21-samd21e16b-sporadically-locks-and-does-not-wake-standby-sleep-mode 47 | SysTick->CTRL &= ~SysTick_CTRL_TICKINT_Msk; 48 | SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk; 49 | __DSB(); 50 | __WFI(); 51 | // Enable systick interrupt 52 | SysTick->CTRL |= SysTick_CTRL_TICKINT_Msk; 53 | if (restoreUSBDevice) { 54 | USBDevice.attach(); 55 | } 56 | } 57 | 58 | void ArduinoLowPowerClass::sleep(uint32_t millis) { 59 | setAlarmIn(millis); 60 | sleep(); 61 | } 62 | 63 | void ArduinoLowPowerClass::deepSleep() { 64 | sleep(); 65 | } 66 | 67 | void ArduinoLowPowerClass::deepSleep(uint32_t millis) { 68 | sleep(millis); 69 | } 70 | 71 | void ArduinoLowPowerClass::setAlarmIn(uint32_t millis) { 72 | 73 | if (!rtc.isConfigured()) { 74 | attachInterruptWakeup(RTC_ALARM_WAKEUP, NULL, (irq_mode)0); 75 | } 76 | 77 | uint32_t now = rtc.getEpoch(); 78 | rtc.setAlarmEpoch(now + millis/1000); 79 | rtc.enableAlarm(rtc.MATCH_YYMMDDHHMMSS); 80 | } 81 | 82 | void ArduinoLowPowerClass::attachInterruptWakeup(uint32_t pin, voidFuncPtr callback, irq_mode mode) { 83 | 84 | if (pin > PINS_COUNT) { 85 | // check for external wakeup sources 86 | // RTC library should call this API to enable the alarm subsystem 87 | switch (pin) { 88 | case RTC_ALARM_WAKEUP: 89 | rtc.begin(false); 90 | rtc.attachInterrupt(callback); 91 | /*case UART_WAKEUP:*/ 92 | } 93 | return; 94 | } 95 | 96 | EExt_Interrupts in = g_APinDescription[pin].ulExtInt; 97 | if (in == NOT_AN_INTERRUPT || in == EXTERNAL_INT_NMI) 98 | return; 99 | 100 | //pinMode(pin, INPUT_PULLUP); 101 | attachInterrupt(pin, callback, mode); 102 | 103 | configGCLK6(); 104 | 105 | // Enable wakeup capability on pin in case being used during sleep 106 | EIC->WAKEUP.reg |= (1 << in); 107 | } 108 | 109 | void ArduinoLowPowerClass::attachAdcInterrupt(uint32_t pin, voidFuncPtr callback, adc_interrupt mode, uint16_t lo, uint16_t hi) 110 | { 111 | uint8_t winmode = 0; 112 | 113 | switch (mode) { 114 | case ADC_INT_BETWEEN: winmode = ADC_WINCTRL_WINMODE_MODE3; break; 115 | case ADC_INT_OUTSIDE: winmode = ADC_WINCTRL_WINMODE_MODE4; break; 116 | case ADC_INT_ABOVE_MIN: winmode = ADC_WINCTRL_WINMODE_MODE1; break; 117 | case ADC_INT_BELOW_MAX: winmode = ADC_WINCTRL_WINMODE_MODE2; break; 118 | default: return; 119 | } 120 | 121 | adc_cb = callback; 122 | 123 | configGCLK6(); 124 | 125 | // Configure ADC to use GCLK6 (OSCULP32K) 126 | while (GCLK->STATUS.bit.SYNCBUSY) {} 127 | GCLK->CLKCTRL.reg = GCLK_CLKCTRL_ID_ADC 128 | | GCLK_CLKCTRL_GEN_GCLK6 129 | | GCLK_CLKCTRL_CLKEN; 130 | while (GCLK->STATUS.bit.SYNCBUSY) {} 131 | 132 | // Set ADC prescaler as low as possible 133 | ADC->CTRLB.bit.PRESCALER = ADC_CTRLB_PRESCALER_DIV4; 134 | while (ADC->STATUS.bit.SYNCBUSY) {} 135 | 136 | // Configure window mode 137 | ADC->WINLT.reg = lo; 138 | ADC->WINUT.reg = hi; 139 | ADC->WINCTRL.reg = winmode; 140 | while (ADC->STATUS.bit.SYNCBUSY) {} 141 | 142 | // Enable window interrupt 143 | ADC->INTENSET.bit.WINMON = 1; 144 | while (ADC->STATUS.bit.SYNCBUSY) {} 145 | 146 | // Enable ADC in standby mode 147 | ADC->CTRLA.bit.RUNSTDBY = 1; 148 | while (ADC->STATUS.bit.SYNCBUSY) {} 149 | 150 | // Enable continuous conversions 151 | ADC->CTRLB.bit.FREERUN = 1; 152 | while (ADC->STATUS.bit.SYNCBUSY) {} 153 | 154 | // Configure input mux 155 | ADC->INPUTCTRL.bit.MUXPOS = g_APinDescription[pin].ulADCChannelNumber; 156 | while (ADC->STATUS.bit.SYNCBUSY) {} 157 | 158 | // Enable the ADC 159 | ADC->CTRLA.bit.ENABLE = 1; 160 | while (ADC->STATUS.bit.SYNCBUSY) {} 161 | 162 | // Start continuous conversions 163 | ADC->SWTRIG.bit.START = 1; 164 | while (ADC->STATUS.bit.SYNCBUSY) {} 165 | 166 | // Enable the ADC interrupt 167 | NVIC_EnableIRQ(ADC_IRQn); 168 | } 169 | 170 | void ArduinoLowPowerClass::detachAdcInterrupt() 171 | { 172 | // Disable the ADC interrupt 173 | NVIC_DisableIRQ(ADC_IRQn); 174 | 175 | // Disable the ADC 176 | ADC->CTRLA.bit.ENABLE = 0; 177 | while (ADC->STATUS.bit.SYNCBUSY) {} 178 | 179 | // Disable continuous conversions 180 | ADC->CTRLB.bit.FREERUN = 0; 181 | while (ADC->STATUS.bit.SYNCBUSY) {} 182 | 183 | // Disable ADC in standby mode 184 | ADC->CTRLA.bit.RUNSTDBY = 1; 185 | while (ADC->STATUS.bit.SYNCBUSY) {} 186 | 187 | // Disable window interrupt 188 | ADC->INTENCLR.bit.WINMON = 1; 189 | while (ADC->STATUS.bit.SYNCBUSY) {} 190 | 191 | // Disable window mode 192 | ADC->WINCTRL.reg = ADC_WINCTRL_WINMODE_DISABLE; 193 | while (ADC->STATUS.bit.SYNCBUSY) {} 194 | 195 | // Restore ADC prescaler 196 | ADC->CTRLB.bit.PRESCALER = ADC_CTRLB_PRESCALER_DIV512_Val; 197 | while (ADC->STATUS.bit.SYNCBUSY) {} 198 | 199 | // Restore ADC clock 200 | while (GCLK->STATUS.bit.SYNCBUSY) {} 201 | GCLK->CLKCTRL.reg = GCLK_CLKCTRL_ID_ADC 202 | | GCLK_CLKCTRL_GEN_GCLK0 203 | | GCLK_CLKCTRL_CLKEN; 204 | while (GCLK->STATUS.bit.SYNCBUSY) {} 205 | 206 | adc_cb = nullptr; 207 | } 208 | 209 | void ADC_Handler() 210 | { 211 | // Clear the interrupt flag 212 | ADC->INTFLAG.bit.WINMON = 1; 213 | LowPower.adc_cb(); 214 | } 215 | 216 | ArduinoLowPowerClass LowPower; 217 | 218 | #endif // ARDUINO_ARCH_SAMD 219 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU LESSER GENERAL PUBLIC LICENSE 2 | Version 2.1, February 1999 3 | 4 | Copyright (C) 1991, 1999 Free Software Foundation, Inc. 5 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 6 | Everyone is permitted to copy and distribute verbatim copies 7 | of this license document, but changing it is not allowed. 8 | 9 | (This is the first released version of the Lesser GPL. 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