UM0224 datasheet(19/34 Pages) STMICROELECTRONICS

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STR75x demonstration software

Running the demonstrations

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STANDBY

This menu allows you to put the STR750 in STANDBY mode. The software performs the

specific sequence of instructions needed to enter STANDBY mode. STANDBY mode is

characterized by:

●

The main voltage regulator is disabled

●

Only the backup circuitry remains powered by the low power voltage regulator

●

Minimum power consumption

●

All registers and SRAM contents are lost

In this application, there are two ways to make the STR750 exit from STANDBY mode:

●

In the first one, the Wake-up push button is used to wake-up the MCU from STANDBY

mode. The following message is displayed on the LCD:

The red LEDs continue blinking until the "SEL" push button is pressed, then the system

enters STANDBY mode and the following message is displayed on the LCD:

The MCU will remain in STANDBY mode unless the Wakeup push button is pressed. Once

this button is pressed, the MCU exits from STANDBY mode and system reset signal is

generated.

●

In the second case, the RTC Alarm will wake-up the MCU from STANDBY mode after

the programmed timing. The following message is displayed on the LCD:

The red LEDs continue blinking until the "SEL" push button is pressed, then the system

enters STANDBY mode and the following message is displayed on the LCD:

After the programmed timing have elapsed, the system exits from the STANDBY mode and

system reset signal is generated.

Exit: WAKEUP Pin

STANDBY Mode

Press WAKEUP Key

STANDBY Mode

Exit: RTC Alarm

STANDBY Mode

Wait for Alarm

STANDBY Mode

UM0224 Datasheet(PDF) 19 Page - STMicroelectronics