Renesas rl78 User Manual
RL78/G1A
CHAPTER 5 CLOCK GENERATOR
R01UH0305EJ0200 Rev.2.00
149
Jul 04, 2013
Figure 5-5. Format of Oscillation Stabilization Time Counter Status Register (OSTC)
Address: FFFA2H After reset: 00H R
Symbol
7 6 5 4 3 2 1 0
OSTC MOST
8
MOST
9
MOST
10
MOST
11
MOST
13
MOST
15
MOST
17
MOST
18
Oscillation stabilization time status
MOST
8
MOST
9
MOST
10
MOST
11
MOST
13
MOST
15
MOST
17
MOST
18
f
X
= 10 MHz
f
X
= 20 MHz
0 0 0 0 0 0 0 0
2
8
/f
X
max.
25.6
μs max. 12.8 μs max.
1 0 0 0 0 0 0 0
2
8
/f
X
min.
25.6
μs min. 12.8 μs min.
1 1 0 0 0 0 0 0
2
9
/f
X
min.
51.2
μs min. 25.6 μs min.
1 1 1 0 0 0 0 0
2
10
/f
X
min.
102
μs min. 51.2 μs min.
1 1 1 1 0 0 0 0
2
11
/f
X
min.
204
μs min. 102 μs min.
1 1 1 1 1 0 0 0
2
13
/f
X
min.
819
μs min. 409 μs min.
1 1 1 1 1 1 0 0
2
15
/f
X
min.
3.27 ms min. 1.63 ms min.
1 1 1 1 1 1 1 0
2
17
/f
X
min.
13.1 ms min. 6.55 ms min.
1 1 1 1 1 1 1 1
2
18
/f
X
min.
26.2 ms min. 13.1 ms min.
Cautions 1. After the above time has elapsed, the bits are set to 1 in order from the MOST8 bit
and remain 1.
2. The oscillation stabilization time counter counts up to the oscillation stabilization
time set by the oscillation stabilization time select register (OSTS).
In the following cases, set the oscillation stabilization time of the OSTS register to
the value greater than the count value which is to be checked by the OSTC register.
• If the X1 clock starts oscillation while the high-speed on-chip oscillator clock or
subsystem clock is being used as the CPU clock.
• If the STOP mode is entered and then released while the high-speed on-chip
oscillator clock is being used as the CPU clock with the X1 clock oscillating.
(Note, therefore, that only the status up to the oscillation stabilization time set by
the OSTS register is set to the OSTC register after the STOP mode is released.)
3. The X1 clock oscillation stabilization wait time does not include the time until clock
oscillation starts (“a” below).
STOP mode release
X1 pin voltage
waveform
waveform
a
Remark f
X
: X1 clock oscillation frequency
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