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.

The EXT4 extension board includes a circuit to manage low-power mode.

Configure

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

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

Use

cpp myScreen.begin();

begin()

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

cpp 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.

cpp 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.

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

hV_HAL_Serial_printf("Power on");
hV_HAL_Serial_crlf();
hV_HAL_delayMilliseconds(4000);

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

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

hV_HAL_Serial_printf("End");
hV_HAL_Serial_crlf();
myScreen.regenerate();

} ```