Infineon XC800 Series, Руководство пользователя

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AP08056
Power Saving Features
Power Down of the Entire System (Power-Down Mode)
Application Note 15 V1.0, 2006-12
If bit WKSEL was cleared to 0 before entering power-down mode, a fast wake-up
sequence is used. The port pins continue to hold their state which was valid during
power-down mode until they are affected by program execution.
The example below shows how the previous example can restore the port 3 status after
exiting the power-down mode with reset.
//... after initialization
SCU_PAGE = 0x01;//Open SCU page 1 to access PMCON0
if (PMCON0 & 0x20)//Check PMCON0.WKRS for wakeup indication
{
SP = STACKSP;//Restore stack pointer, SP = 0x42
PORT_PAGE = 0x00; //Open port page 0 to access Px_DATA
_pop_(P3_DATA); //Restore P3 from stack
}
//... continue...
Table 7 illustrates the timing for a device to wake-up from power-down mode to active
mode for both wake-up with/without reset.
In power-down mode, the typical amount of current drawn by the devices will be
approximately 1 µA at 25
o
C.
Table 7 Wakeup timing from power-down mode
XC866-1FR XC866-4FR and
XC886/888
Reset Sequence WKSEL = 1 WKSEL = 0 WKSEL = 1 WKSEL = 0
EVR is stable 150 µs (Typical) 150 µs (Typical)
PLL is locked 200 µs (Maximum) 200 µs (Maximum)
Flash ready to read
state 0 160 µs 0 160 µs
BROM execution
1)
1) Timing is based on the system frequency of the devices. XC866 operates at 80 MHz while XC886/888
operates at 96 MHz.
0 215 µs
(Typical)
0 250 µs
(Typical)
Total wake-up time 350 µs 725 µs 350 µs 760 µs