Toshiba TLCS-870/C Series Manual page 35

2. Operational Description
2.2 System Clock Controller
STOP mode is released by the following sequence.
1. In the dual-clock mode, when returning to NORMAL2, both the high-frequency and low-
frequency clock oscillators are turned on; when returning to SLOW1 mode, only the low-
frequency clock oscillator is turned on. In the single-clock mode, only the high-frequency
clock oscillator is turned on.
2. A warm-up period is inserted to allow oscillation time to stabilize. During warm up, all
internal operations remain halted. Four different warm-up times can be selected with the
SYSCR1<WUT> in accordance with the resonator characteristics.
3. When the warm-up time has elapsed, normal operation resumes with the instruction follow-
ing the STOP mode start instruction.
Note 1: When the STOP mode is released, the start is made after the prescaler and the divider of the
timing generator are cleared to "0".
Note 2: STOP mode can also be released by inputting low level on the
performs the normal reset operation.
Note 3: When STOP mode is released with a low hold voltage, the following cautions must be observed.
The power supply voltage must be at the operating voltage level before releasing STOP mode.
The pin input must also be "H" level, rising together with the power supply voltage. In this
RESET
case, if an external time constant circuit has been connected, the
increase at a slower pace than the power supply voltage. At this time, there is a danger that a
reset may occur if input voltage level of the
input voltage (Hysteresis input).
Table 2-2 Warm-up Time Example (at fc = 16.0 MHz, fs = 32.768 kHz)
WUT
Return to NORMAL Mode
00
01
10
11
Note 1: The warm-up time is obtained by dividing the basic clock by the divider. Therefore, the warm-up
time may include a certain amount of error if there is any fluctuation of the oscillation frequency
when STOP mode is released. Thus, the warm-up time must be considered as an approximate
value.
pin drops below the non-inverting high-level
RESET
Warm-up Time [ms]
Return to SLOW Mode
12.288
4.096
3.072
1.024
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TMP86PM29BUG
pin, which immediately
RESET
pin input voltage will
RESET
750
250
5.85
1.95