UM0224 datasheet(18/34 Pages) STMICROELECTRONICS

18 / 34 page

Running the demonstrations

STR75x demonstration software

18/34

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

●

In the first one, the EXTIT (Key button) is used to exit the MCU from STOP 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 STOP mode and the following message is displayed on the LCD:

The MCU will remain in STOP mode unless the Key push button is pressed. Once this

button is pressed, the MCU exits from STOP mode. Then the system clock is set to 60 MHz

and the application resumes executing.

Note:

If an alarm occurs when the system is in STOP mode, the following message is displayed on

the LCD screen when the MCU resumes from STOP mode:

●

In the second case, the RTC Alarm will wake-up the MCU from STOP 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 STOP mode and the following message is displayed on the LCD:

After the programmed timing has elapsed, the system exits from STOP mode. Then the

system clock is set to 60 MHz and the application resumes executing.

Note:

In both cases, the NCKD flag will wake-up the MCU from STOP mode.

Exit: EXTIT/NCKD

STOP Mode

Exit:Press Key

STOP Mode

One missed Alarm

Exit:Press SEL

Exit: Alarm/NCKD

STOP Mode

Wait for Alarm

STOP Mode

UM0224 Datasheet(PDF) 18 Page - STMicroelectronics