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Manage low-power mode

Manage low-power mode

An optional external circuit can manage low-power mode. A dedicated signal drives it to enter and exit low-power mode.

Configure

Ensure the panelPower pin is set to a value other than NOT_CONNECTED.

const pins_t myBoard =
{
    // ...
    .panelPower = 12, ///< Optional power circuit 
    // ...
};

Use

myScreen.begin();

begin() resets and configures the panel. By default, the panel is powered on.

myScreen.suspend();

suspend() sets all the GPIOs to LOW; deactivates the SPI bus; and enters low-power mode by turning off the power of the panel.

myScreen.resume();

resume() restores all the GPIOs; reactivates the SPI bus; exits low-power mode by turning on the power; then resets and configures the panel.

Warning

The functions suspend() and resume() should not be used if other devices share the same SPI bus.

Example

The example below shows three states: panel is powered on for 4 seconds; panel is refreshed; panel is powered off for 4 seconds.

void displayPower()
{
    myScreen.setOrientation(myOrientation);

    hV_HAL_Debug_println("Power on");
    hV_HAL_delayMilliseconds(4000);

    hV_HAL_Debug_println("Refresh");
    myScreen.clear();
    myScreen.gText(4, 4, "Refresh");
    myScreen.flush();

    hV_HAL_Debug_println("Power off");
    myScreen.suspend();
    hV_HAL_delayMilliseconds(4000);
    myScreen.resume();

    hV_HAL_Debug_println("End");
    myScreen.regenerate();
}