PFS172 datasheet(53/92 Pages) PADAUK

53 / 92 page

PFS172

8bit MTP MCU with 8-bit ADC

Page 53 of 92

PDK-DS-PFS172-EN_V000-May 8, 2020

5.10 Power-Save and Power-Down

There are three operational modes defined by hardware: ON mode, Power-Save mode and Power-Down

modes. ON mode is the state of normal operation with all functions ON, Power-Save mode (“stopexe”) is the

state to reduce operating current and CPU keeps ready to continue, Power-Down mode (“stopsys”) is used

to save power deeply. Therefore, Power-Save mode is used in the system which needs low operating power

with wake-up periodically and Power-Down mode is used in the system which needs power down deeply with

seldom wake-up.

5.10.1

Power-Save mode (“stopexe”)

Using “stopexe” instruction to enter the Power-Save mode, only system clock is disabled, remaining all

the oscillator modules active. For CPU, it stops executing; however, for Timer16, counter keep counting

if its clock source is not the system clock. The wake-up sources for “stopexe” can be IO-toggle or

Timer16 counts to set values when the clock source of Timer16 is IHRC or ILRC modules, or wake-up

by comparator when setting GPCC.7=1 and GPCS.6=1 to enable the comparator wake-up function at

the same time. Wake-up from input pins can be considered as a continuation of normal execution, the

detail information for Power-Save mode shows below:

 IHRC and EOSC oscillator modules: No change, keep active if it was enabled.

 ILRC oscillator modules: must remain enabled, need to start with ILRC when be wakening up.

 System clock: Disable, therefore, CPU stops execution.

 MTP memory is turned off.

 Timer counter: Stop counting if system clock is selected or the corresponding oscillator module is

disabled; otherwise, it keeps counting. (The Timer contains TM16, TM2, TM3.)

 Wake-up sources:

a. IO toggle wake-up: IO toggling in digital input mode (PxC bit is 1 and PxDIER bit is 1)

b. Timer wake-up: If the clock source of Timer is not the SYSCLK, the system will be awakened

when the Timer counter reaches the set value.

c. Comparator wake-up: It need setting GPCC.7=1 and GPCS.6=1 to enable the comparator

wake-up function at the same time.

An example shows how to use Timer16 to wake-up from “stopexe”:

$ T16M

ILRC, /1, BIT8

// Timer16 setting

$ INTEGS

BIT_R, xxx;

// BITx 0 to 1 will trigger (default)

…

WORD

count =

STT16

count;

stopexe;

…

The initial counting value of Timer16 is zero and the system will be woken up after the Timer16 counts

256 ILRC clocks.

PFS172 датащи(PDF) 53 Page - PADAUK Technology.

PFS172 датащи(HTML) 53 Page - PADAUK Technology.

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92

датащи скачать

ссылки URL