105
5.3.3
Oscillator Settling Time after Standby Mode is Cleared
Bits STS2 to STS0 in SYSCR1 should be set as follows.
• When a crystal oscillator is used
The table below gives settings for various operating frequencies. Set bits STS2 to STS0 for a
waiting time at least as long as the oscillation settling time.
Table 5.4
Clock Frequency and Settling Time (times are in ms)
STS2
STS1
STS0
Waiting Time
10 MHz
2 MHz
1 MHz
0
0
0
8,192 states
0.82
4.1
8.2
0
0
1
16,384 states
1.64
8.2
16.4
0
1
0
32,768 states
3.28
16.4
32.8
0
1
1
65,536 states
6.56
32.8
65.5
1
0
0
131,072 states
13.1
65.5
131.1
1
0
1
2 states
(Use prohibited)
0.0002
0.001
0.002
1
1
0
8 states
0.0008
0.004
0.008
1
1
1
16 states
0.0016
0.008
0.016
• When an external clock is used
STS2 = 1, STS1 = 0, and STS0 = 1 should be set. Other values possible use, but CPU sometimes
will start operation before waiting time completion.