
R01UH0040EJ0100 Rev.1.00
Page 209 of 1657
Sep 8, 2011
RX630 Group
7. Option-Setting Memory
7.2.2
Option Function Select Register 1 (OFS1)
The OFS1 register is allocated in the ROM. Set this register at the same time as writing the program. After writing, do
not write additions to this register.
When erasing the block including the OFS1 register, the setting in the OFS1 register is ineffective, and the OFS1 register
value becomes FFFF FFFFh.
The setting in the OFS1 register is ineffective in user boot mode and USB boot mode, and the value becomes FFFF
FFFFh.
LVDAS Bit (Voltage Detection 0 Circuit Start)
This bit selects whether the voltage monitor 0 reset is enabled or disabled after a reset.
HOCOEN Bit (HOCO Oscillation Enable)
This bit selects whether the HOCO oscillation enable bit is effective or not after a reset.
Setting the HOCOEN bit to 0 allows the HOCO oscillation to be started before the CPU starts operation, and therefore
reduces the waiting time for oscillation stabilization.
Note that even if the HOCOEN bit is set to 0, the system clock source is not switched to HOCO. The system clock source
is switched to HOCO only by modifying the clock source select bits (SCKCR3.CKSEL[2:0]) from the CPU.
Address(es): FFFF FF88h
b31
b30
b29
b28
b27
b26
b25
b24
b23
b22
b21
b20
b19
b18
b17
b16
——————
————
Value after reset:
The value set by the user*1
b15
b14
b13
b12
b11
b10
b9
b8
b7
b6
b5
b4
b3
b2
b1
b0
——————
—
HOCO
EN
————
—
LVDAS
——
Value after reset:
The value set by the user*1
Note 1. The value of the blank product is FFFF FFFFh. It is set to the written value after written by the user.
Bit
Symbol
Bit Name
Description
R/W
b1, b0
—
Reserved
When reading, this bit returns to the value written by the user.
The write value should be 1.
R
b2
Voltage Detection 0 Circuit
Start
0: Voltage monitor 0 reset is enabled after a reset
1: Voltage monitor 0 reset is disabled after a reset
R
b7 to b3
—
Reserved
When reading, this bit returns to the value written by the user.
The write value should be 1.
R
b8
HOCO Oscillation Enable
0: HOCO oscillation is enabled after a reset
1: HOCO oscillation is disabled after a reset
R
b31 to b9
—
Reserved
When reading, this bit returns to the value written by the user.
The write value should be 1.
R