High-Speed On-Chip Oscillator Frequency Select Register (Hocodiv) - Renesas RL78/G1P Hardware User Manual

RL78/G1P

5.3.7 High-speed on-chip oscillator frequency select register (HOCODIV)

The frequency of the high-speed on-chip oscillator which is set by an option byte (000C2H) can be changed by using
high-speed on-chip oscillator frequency select register (HOCODIV). However, the selectable frequency depends on the
FRQSEL3 bit of the option byte (000C2H).
The HOCODIV register can be set by an 8-bit memory manipulation instruction.
Reset signal generation clears this register to the value set by FRQSEL2 to FRQSEL0 of the option byte (000C2H).
Figure 5-9. Format of High-speed On-chip Oscillator Frequency Select Register (HOCODIV)
Address: F00A8H
Symbol 7
0
HOCODIV
HOCOD
IV2
0
0
0
0
1
1
Cautions 1. Set the HOCODIV register within the operable voltage range of the flash operation
Option Byte (000C2H)
CMODE1
R01UH0895EJ0100 Rev.1.00
Nov 29, 2019
After reset: the value set by FRQSEL2 to FRQSEL0 of the option byte (000C2H)
6 5
0 0
HOCOD HOCOD
IV1 IV0
0 0
0 1
1 0
1 1
0 0
0 1
Other than above
mode set in the option byte (000C2H) before and after the frequency change.
Value
CMODE0
1 0 LS (low-speed main) mode
1 1 HS (high-speed main) mode
2. Set the HOCODIV register with the high-speed on-chip oscillator clock (f
selected as the CPU/peripheral hardware clock (f
3. After the frequency is changed with the HOCODIV register, the frequency is
switched after the following transition time has elapsed.
 Operation for up to three clocks at the pre-change frequency
 CPU/peripheral hardware clock wait at the post-change frequency for up to
three clocks
4 3
0 0
High-Speed On-Chip Oscillator Clock Frequency
FRQSEL3 Bit is 0
24 MHz
12 MHz
6 MHz
3 MHz
Setting prohibited
Setting prohibited
Setting prohibited
Flash Operation Mode
CHAPTER 5 CLOCK GENERATOR
R/W
2 1
HOCODIV2 HOCODIV1 HOCODIV0
FRQSEL3 Bit is 1
32 MHz
16 MHz
8 MHz
4 MHz
2 MHz
1 MHz
Operating Operating Voltage
Frequency Range
1 to 8 MHz 2.7 to 3.6 V
1 to 32 MHz 2.7 to 3.6 V
).
CLK
0
Range
)
IH
109