Power Management

Functions related to power management might involve registers of the IP5306 chip. For any uncertainties, you can refer to the IP5306 register manual.

The IP5306 chip does not support communication with older M5STACK hardware. When using features, also consider support for uncontrollable situations.

Use in order: initialization, communication check, and control, as shown in the example below:

  M5.Power.begin();
  if(!M5.Power.canControl()) {
    //can't control.
    return;
  }
  M5.Power.lightSleep(SLEEP_SEC(5));

begin()

Description:

Initializes the Power class.

Syntax:

void begin();

Example:

#include <M5Stack.h>

void setup() {
    M5.begin();
    M5.Power.begin();
}

void loop() {}

setPowerBoostOnOff()

Description:

Changes the method of turning the device on/off with the power button.

Syntax:

bool setPowerBoostOnOff(bool en);

Return Value:

Example:

#include <M5Stack.h>

void setup() {
    M5.begin();
    M5.Power.begin();
    if (M5.Power.setPowerBoostOnOff(false)) {
        M5.Lcd.println("Changed power on/off method");
    } else {
        M5.Lcd.println("Failed to change power on/off method");
    }
}

void loop() {}

setPowerBoostKeepOn()

Description:

Changes the power on/off method. The power will not turn off when connected via USB.

Syntax:

bool setPowerBoostKeepOn(bool en);

Return Value:

setPowerVin()

Description:

Decides whether to power on again when external sources like USB are disconnected.

Syntax:

bool setPowerVin(bool en);

Return Value:

setPowerWLEDSet()

Description:

Sets the mode to turn on the power LED. Not controllable via this function for M5GO due to lack of wiring to IP5306.

Syntax:

bool setPowerWLEDSet(bool en);

Return Value:

setPowerBtnEn()

Description:

Sets whether to accept power button actions.

Regarding behavior when not accepting button actions: If the power is on, the power button only accepts CPU reset. If no power is provided, it's not possible to turn the power on.

Syntax:

bool setPowerBtnEn(bool en);

Return Value:

setLowPowerShutdownTime()

Description:

Sets the wait time until IP5306 decides to save energy and turns off the power.

Syntax:

bool setLowPowerShutdownTime(ShutdownTime time);

Return Value:

| Value | Function

| ality | | ----- | ----------------- | | true | Control succeeded | | false | Control failed |

setPowerBoostKeepOn()

Description:

This function enables/disables the always-on boost output mode.

Syntax:

bool setPowerBoostKeepOn(bool en);

Return Value:

setAutoBootOnLoad()

Description:

Sets whether to auto-boot when there is a power consumption on the secondary side of IP5306.

Syntax:

bool setAutoBootOnLoad(bool en);

Return Value:

setCharge()

Description:

This function enables/disables charging mode. After the battery is full, toggling charge enable -> disable -> enable may allow charging to resume.

Syntax:

bool setCharge(bool en);

Return Value:

isChargeFull()

Description:

Checks if the battery is fully charged.

Syntax:

bool isChargeFull();

Return Value:

canControl()

Description:

This function checks if the battery controller is present via I2C communication.

Syntax:

bool canControl();

Return Value:

isCharging()

Description:

Checks if charging is in progress.

Syntax:

bool isCharging();

Return Value:

getBatteryLevel()

Description:

Returns the battery level.

Syntax:

int8_t getBatteryLevel();

Return Value:

Returns battery level as 0/25/50/75/100. Returns -1 if unable to check the remaining capacity.

setWakeupButton()

Description:

Sets the wake-up port upon sleep return.

Syntax:

void setWakeupButton(uint8_t button);

Example:

setWakeupButton(BUTTON_A_PIN);

reset()

Description:

Performs a CPU reset.

Syntax:

void reset();

isResetbySoftware()

Description:

Determines if the current activation state is after a CPU reset. (Applies if executing reset() or an equivalent process such as RTOS.)

Syntax:

bool isResetbySoftware();

Return Value:

isResetbyWatchdog()

Description:

Determines if the current activation state is after a watchdog timer.

Syntax:

bool isResetbyWatchdog();

Return Value:

isResetbyDeepsleep()

Description:

Determines if the current wake state is after deepSleep().

Syntax:

bool isResetbyDeepsleep();

Return Value:

isResetbyPowerSW()

Description:

Determines if the current start-up state is after turning on the power switch.

Syntax:

bool isResetbyPowerSW();

Return Value:

deepSleep()

Description:

This function transitions to deep sleep mode. It wakes up after a specified time or

when a port state changes. Upon wake-up, the CPU restarts, not running from the next line.

Syntax:

void deepSleep();

Example:

To save power for 5 seconds then restart:

deepSleep(SLEEP_SEC(5));

lightSleep()

Description:

This function transitions to light sleep mode. It wakes up after a specified time or when a port changes. Upon returning, it runs from the next line. Compared to deepSleep(), it lacks power-saving functionality.

Syntax:

void lightSleep(uint64_t time_in_us);

Example:

To save power for 5 seconds then restart:

lightSleep(SLEEP_SEC(5));

powerOFF()

Description:

Turns off the power. Uses the power-saving feature to turn off IP5306 after 8 seconds. Shuts off power provided to the circuit side.

Syntax:

void powerOFF();