Renesas RL78/G1H

RL78/G1H CHAPTER 6 CLOCK GENERATOR
R01UH0575EJ0120 Rev. 1.20 Page 124 of 920
Dec 22, 2016
6.6 Controlling Clock
6.6.1 Example of setting high-speed on-chip oscillator
After a reset release, the CPU/peripheral hardware clock (fCLK) always starts operating with the high-speed on-
chip oscillator clock. The frequency of the high-speed on-chip oscillator can be selected from 32, 24, 16, 12, 8, 6,
4, 3, 2, and 1 MHz by using FRQSEL0 to FRQSEL3 of the option byte (000C2H). In addition, Oscillation can be
changed by the high-speed on-chip oscillator frequency select register (HOCODIV).
[Option byte setting]
Address: 000C2H
Option
byte
(000C2H)
76543210
1
CMODE0
0/1 1 0
FRQSEL3
0/1
FRQSEL2
0/1
FRQSEL1
0/1
FRQSEL0
0/1
CMODE0 Flash operation mode Operating frequency range Operating voltage range
0 LS (low-speed main) mode 1 MHz to 8 MHz 1.8 V to 3.6 V
1 HS (high-speed main) mode
1 MHz to 16 MHz 2.4 V to 3.6 V
1 MHz to 32 MHz 2.7 V to 3.6 V
FRQSEL3 FRQSEL2 FRQSEL1 FRQSEL0
Frequency of the high-speed on-chip oscillator
f
IH
1000 32 MHz
0000 24 MHz
1000 32 MHz
0000 24 MHz
1001 16 MHz
0001 12 MHz
1010 8 MHz
0010 6 MHz
1011 4 MHz
0011 3 MHz
1100 2 MHz
1101 1 MHz
Other than above Setting prohibited
<R>