GMS81C50 Datasheet, PDF (75/99 Pages) Hynix Semiconductor – 8-BIT SINGLE CHIP MICROCONTROLLERS

GMS81C50 Series
HYUNDAI
[ SLEEP MODE ]
Xin
release by interrupt
RESET
SLEEP command
SLEEP Mode
Longer than
2 machine cycle
[ STOP MODE ]
clock
release by interrupt
RESET
STOP Mode
Stable
OSC. time
Program Setting Time by
CKCTLR
Longer than
stable OSC. Time
Figure 14-3 Release Timing of Standby Mode
14.4 RELEASE OPERATION OF STANDBY MODE
After standby mode is released, the operation begins ac-
cording to content of related interrupt register just before
standby mode start (Figure 14-4 )
(1) Interrupt Enable Flag(I) of PSW = ``0``
Release by only interrupt which interrupt enable flag =
``1``, and starts to execute from next to standby instruction
(SLEEP or STOP).
(2) Interrupt Enable Flag(I) of PSW = ``1``
= ``1``, and jump to the relevant interrupt service routine.
Note: When STOP instruction is used, B.I.T should guar-
antee the stabilization oscillation time. Thus, just before en-
tering STOP mode, clock of bit10 (PS10) of prescaler is
selected or peripheral hardware clock control bit (ENPCK)
to ``1``, Therefore the clock necessary for stabilization os-
cillation time should be input into B.I.T. otherwise, standby
mode is released by reset signal. In case of interrupt re-
quest flag and interrupt enable flag are both ``1``, standby
mode is not entered.
Released by only interrupt which each interrupt enable flag
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