CHAPTER 15 STANDBY FUNCTION
User’s Manual U14826EJ5V0UD
149
15.1.2 Standby function control register
The wait time after STOP mode is released upon interrupt request until the oscillation stabilizes is controlled with
the oscillation stabilization time selection register (OSTS)
Note
.
OSTS is set with an 8-bit memory manipulation instruction.
RESET input sets OSTS to 04H.
However, the oscillation stabilization time after RESET release varies for each product not depending on the
OSTS.
µ
PD789860: Oscillation
stabilization
time can be selected from 2
15
/f
X
or 2
17
/f
X
by mask option.
µ
PD78E9860A:
Oscillation stabilization time is fixed to 2
15
/f
X
and cannot be selected by mask option.
µ
PD789861, 78E9861A: Oscillation stabilization time is fixed to 2
7
/f
CC
and cannot be selected by mask option.
Note
µ
PD789860 Subseries only.
There is no oscillation stabilization time selection register in the
µ
PD789861 Subseries. The oscillation
stabilization time of the
µ
PD789861 Subseries is fixed at 2
7
/f
CC
.
Figure 15-1. Format of Oscillation Stabilization Time Selection Register
OSTS2
0
0
1
OSTS1
0
1
0
2
12
/f
X
2
15
/f
X
2
17
/f
X
(819 s)
(6.55 ms)
(26.2 ms)
OSTS0
0
0
0
Setting prohibited
Oscillation stabilization time selection
Other than above
µ
0
0
0
0
OSTS1
OSTS2
0
OSTS0
OSTS
7
6
5
4
3
2
1
0
Symbol
Address
After reset
R/W
FFFAH
04H
R/W
Caution The wait time after STOP mode is released does not include the time from STOP mode release to
clock oscillation start (“a” in the figure below), regardless of release by RESET input or by
interrupt generation.
STOP mode release
X1 pin voltage
waveform
a
Remarks 1.
f
X
: System clock oscillation frequency (ceramic/crystal oscillation)
2.
The parenthesized values apply to operation at f
X
= 5.0 MHz.