Cypress FM4 Series - Examples of Procedure for Setting Deep Standby Mode

CHAPTER 6: Low Power Consumption Mode
FM4 Peripheral Manual, Doc. No. 002-04856 Rev. *E 225
6. Examples of Procedure for Setting Deep Standby Mode
This section provides examples of procedure for setting a deep standby mode.
Figure 6-1 Example of Procedure for Setting Deep Standby RTC Mode
Notes:
− Before making the CPU transit to deep standby RTC mode, ensure that the Flash memory
automatic algorithm has terminated.
− Writing 1 to the RTCE bit in the RTC Mode Control Register (PMD_CTL) is effective only if the
SORDY bit in the System Clock Mode Status Register (SCM_STR) is “1”.
Write 0x1ACC to KEY, 1 to DSTM, 0b10
to STM in STB_CTL register together.
Write 1 to SLEEPDEEP.
End
Start
Execute WFI instruction or WFE
instruction.
CPU transits to deep standby RTC
mode.
Write 1 to RTCE in PMD_CTL register.