Option Function Select Register 1 (Ofs1) - Renesas RX100 Series User Manual

RX13T Group
7.2.2

Option Function Select Register 1 (OFS1)

Address(es): OFSM.OFS1 FFFF FF88h
b31 b30
— —
Value after reset:
b15 b14
— —
Value after reset:
Bit Symbol
b1, b0 VDSEL[1:0]
b2 LVDAS
b7 to b3 —
b8 HOCOEN
b31 to b9 —
Note 1. The value of the blank product is FFFF FFFFh. This register is set to a specified value after programming of the flash memory
with the user program.
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 OFS1 register value becomes FFFF FFFFh.
The setting in the OFS1 register is ignored in boot mode, and this register functions similarly when it is set to FFFF
FFFFh.
VDSEL[1:0] Bits (Voltage Detection 0 Level Select)
These bits select the voltage detection level to be monitored by the voltage detection 0 circuit.
LVDAS Bit (Voltage Detection 0 Circuit Start)
This bit selects whether the voltage monitoring 0 reset is enabled or disabled after a reset.
The Vdet0 voltage to be monitored by the voltage detection 0 circuit is selected by the VDSEL[1:0] bits.
HOCOEN Bit (HOCO Oscillation Enable)
This bit selects whether the HOCO oscillation 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 wait 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.
Also, when the HOCOEN bit is set to 0, the HOCO oscillation stabilization time (tHOCO) is secured by hardware, so the
clock with the accuracy of the HOCO oscillation frequency (fHOCO) shown in Electrical Characteristics is supplied
after release from the CPU reset state.
R01UH0822EJ0100 Rev.1.00
Jul 31, 2019
b29 b28 b27 b26
— — — —
b13 b12 b11 b10
— — — —
Bit Name
Voltage Detection 0 Level
Select
Voltage Detection 0 Circuit
Start
Reserved
HOCO Oscillation Enable
Reserved
b25 b24 b23 b22
— — — —
1
The value set by the user*
b9 b8 b7 b6
HOCO
— — —
EN
1
The value set by the user*
Description
b1 b0
0 0: 3.84 V is selected
0 1: 2.82 V is selected
1 0: 2.51 V is selected
Settings other than above are prohibited when the voltage
detection 0 circuit is used.
0: Voltage monitoring 0 reset is enabled after a reset
1: Voltage monitoring 0 reset is disabled after a reset
When reading, these bits return the value written by the user.
The write value should be 1.
0: HOCO oscillation is enabled after a reset
1: HOCO oscillation is disabled after a reset
When reading, these bits return the value written by the user.
The write value should be 1.
7. Option-Setting Memory (OFSM)
b21 b20 b19 b18
— — — —
b5 b4 b3 b2
— — — LVDAS
Page 109 of 1041
b17 b16
— —
b1 b0
VDSEL[1:0]
R/W
R
R
R
R
R