Product data

HD404818 Series
29
the next instruction after the SBY instruction. If the interrupt enable flag is 1, that interrupt is then
processed; if it is 0, the interrupt request is left pending and normal instruction execution continues. A
flowchart of operation in standby mode is shown in figure 10.
Standby
Oscillator: Active
Peripheral clocks:
Active
All other clocks:
Stop
RESET
= 1 ?
No
Yes
IF0 =
1 ?
No
Yes
IM0 =
0 ?
IF1 =
1 ?
No
Yes
IM1 =
0 ?
IFTA =
1 ?
No
Yes
IMTA =
0 ?
IFTB =
1 ?
No
Yes
IMTB =
0 ?
IFTC =
1 ?
No
Yes
IMTC =
0 ?
IFS =
1 ?
No
Yes
IMS =
0 ?
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
(SBY only)
(SBY only)
(SBY only)
Watch
Oscillator: Stop
Suboscillator: Active
Peripheral clocks: Stop
All other clocks: Stop
Restart
processor clocks
Reset MCU
Execute
next instruction
Accept interrupt
Execute
next instruction
(active mode)
Restart
processor clocks
No
Yes
IF = 1,
IM = 0, and
IE = 1?
(SBY only)
Figure 10 MCU Operating Flowchart of Watch and Standby Modes