NEC PD750008 - Manual (Page 239)

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CHAPTER 7 STANDBY FUNCTION
Table 7-2. Selection of a Wait Time with BTM
Note This time does not include the time from the release of the STOP mode to the start of oscillation.
Caution The wait times used when the STOP mode is released do not include the time (a in Figure7-
2) required before clock oscillation is started following the release of the STOP mode,
regardless of whether the STOP mode is released by a RESET signal or the generation of
an interrupt.
Figure 7-2. Wait Time When the STOP Mode Is Released
7.3 OPERATION AFTER A STANDBY MODE IS RELEASED
(1) If a standby mode is released by a RESET signal, normal reset operation is performed.
(2) If a standby mode is released by the occurrence of an interrupt request, the contents of the interrupt master
enable flag (IME) determines whether to perform a vectored interrupt when the CPU resumes instruction
execution.
(a) When IME = 0
If a standby mode is released, execution restarts with the instruction immediately following the
instruction used to set the standby mode.
The interrupt request flag is held.
(b) When IME = 1
If a standby mode is released, a vectored interrupt is executed after the two instructions are executed.
However, if the standby mode is released by INT2 or INTW (testable input), no vectored interrupt
occurs, and the same processing as (a) above is performed.
BTM3 BTM2 BTM1 BTM0
( ) indicates the value for f
X
=
4.19 MHz
Wait time Note
Other than above
–
–
–
–
0
0
1
1
0
1
0
1
0
1
1
1
Not to be set
Approx. 2 20 /f
X
(Approx. 250 ms)
Approx. 2 17 /f
X
(Approx. 31.3 ms)
Approx. 2 15 /f
X
(Approx. 7.81 ms)
Approx. 2 13 /f
X
(Approx. 1.95 ms)
Approx. 2 20 /f
X
(Approx. 175 ms)
Approx. 2 17 /f
X
(Approx. 21.8 ms)
Approx. 2 15 /f
X
(Approx. 5.46 ms)
Approx. 2 13 /f
X
(Approx. 1.37 ms)
( ) indicates the value for f
X
=
6.00 MHz
a
STOP mode release
Waveform
at the X1 pin
V
SS