NEC uPD78056Y - Manual (Page 526)

526
CHAPTER 23 STANDBY FUNCTION
Address
FFFAH 04H
After
Reset
R/W
R/W
0
0
0
0
1
Selection of Oscillation Stabilization
Time when STOP Mode is Released
2 12 /f xx
2 14 /f xx
2 15 /f
xx
2 16 /f xx
2 17 /f xx
OSTS2
7
0
Symbol
OSTS
6
0
5
0
4
0
3
0
2
OSTS2
1
OSTS1
0
OSTS0
0
0
1
1
0
Other than above
OSTS1
MCS = 1 MCS = 0
2 12 /f x (819 s)
2 14 /f x (3.28 ms)
2 15 /f
x
(6.55 ms)
2 16 /f x (13.1 ms)
2 17 /f x (26.2 ms)
2 13 /f x (1.64 ms)
2 15 /f x (6.55 ms)
2 16 /f
x
(13.1 ms)
2 17 /f x (26.2 ms)
2 18 /f x (52.4 ms)
m 0
1
0
1
0
OSTS0
Setting prohibited
STOP Mode Clear
X1 Pin
Voltage
Waveform
V SS
a
23.1.2 Standby function control register
A wait time after the STOP mode is cleared upon interrupt request till the oscillation stabilizes is controlled with
the oscillation stabilization time select register (OSTS).
OSTS is set with an 8-bit memory manipulation instruction.
RESET input sets OSTS to 04H. However, it takes 2 17 /f X , not 2 18 /f X , until the STOP mode is cleared by RESET
input.
Figure 23-1. Oscillation Stabilization Time Select Register Format
Caution The wait time after STOP mode clear does not include the time (see "a" in the illustration below)
from STOP mode clear to clock oscillation start, regardless of clearance by RESET input or by
interrupt request generation.
Remarks 1. f XX : Main system clock frequency (f X or f X /2)
2. f
X
: Main system clock oscillation frequency
3. MCS : Bit 0 of oscillation mode select register (OSMS)
4. Values in parentheses apply to operating at f X = 5.0 MHz