Wake-Up Event; Output Port State And Stop And Sleep Mode - Samsung S3C2416 User Manual

S3C2416X RISC MICROPROCESSOR
6.3

WAKE-UP EVENT

When S3C2416 wakes up from the STOP Mode by an External Interrupt, a RTC alarm interrupt and other
interrupts, the PLL is turned on automatically. The initial-state of S3C2416 after wake-up from the SLEEP Mode is
almost the same as the Power-On-Reset state except for the contents of the external DRAM is preserved. In
contrast, S3C2416 automatically recovers the previous working state after wake-up from the STOP Mode. The
following table shows the states of PLLs and internal clocks after wake-ups from the power-saving modes.
Mode before
wake-up
IDLE
STOP
SLEEP
6.4

OUTPUT PORT STATE AND STOP AND SLEEP MODE

Refer to GPIO chapter.
Table 2-7. The Status of PLL and ARMCLK After Wake-up
PLL on/off after
wake-up
Unchanged
PLL state ahead of
entering STOP mode
(PLL ON or not)
Off
SYSCLK after wake-up
and before the lock time
PLL output
PLL reference clock
PLL reference clock
SYSTEM CONTROLLER
SYSCLK after the lock
time by internal logic
PLL output
SYSCLK ahead of entering
STOP mode
(PLL output or not)
PLL reference(input) clock
2-19