Renesas RX Series User Manual

R01UH0823EJ0100 Rev.1.00 Page 1663 of 1823
Jul 31, 2019
RX23W Group 50. Flash Memory (FLASH)
50.4.2 Flash P/E Mode Entry Register (FENTRYR)
To rewrite the ROM or E2 DataFlash, the FENTRYD or FENTRY0 bit must be set to 1 to place the ROM or E2
DataFlash in P/E mode.
When returning to read mode, set the FENTRYR register and confirm that its value has been rewritten before reading the
ROM or E2 DataFlash.
Refer to
section 50.7.1, Sequencer Modes for details on P/E mode and read mode.
FENTRY0 Bit (ROM P/E Mode Entry 0)
This bit is used to place the ROM in P/E mode.
[Setting condition]
 AA01h is written to the FENTRYR register when the FENTRYR register is 0000h.
Note: When entering ROM P/E mode, the instruction fetch address must be transferred to an area other than the ROM
so that instruction fetching is not executed to the ROM. Copy necessary instruction code to the internal RAM and
jump to the RAM. Note that E2 DataFlash can be rewritten by a program in the ROM.
[Clearing condition]
 AA00h is written to the FENTRYR register.
FENTRYD Bit (E2 DataFlash P/E Mode Entry)
This bit is used to place the E2 DataFlash in P/E mode.
[Setting condition]
 AA80h is written to the FENTRYR register when the FENTRYR register is 0000h.
[Clearing condition]
 AA00h is written to the FENTRYR register.
Address(es): FLASH.FENTRYR 007F FFB2h
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
FEKEY[7:0]
FENTR
YD
——————
FENTR
Y0
Value after reset:
0000000000000000
Bit Symbol Bit Name Description R/W
b0 FENTRY0 ROM P/E Mode Entry 0 0: ROM is in read mode.
1: ROM can be placed in P/E mode.
R/W
b6 to b1 — Reserved These bits are read as 0. The write value should be 0. R/W
b7 FENTRYD E2 DataFlash P/E Mode
Entry
0: E2 DataFlash is in read mode.
1: E2 DataFlash can be placed in P/E mode.
R/W
b15 to b8 FEKEY[7:0] Key Code The FEKEY[7:0] bits are used to control rewriting of the FENTRYR
register.
When rewriting the value of the lower 8 bits, set the FEKEY[7:0] bits to
AAh at the same time (write this register in 16 bits).
The FEKEY[7:0] bits are read as 00h.
R/W

Renesas RX Series Specifications

General

Core	RXv1, RXv2, RXv3
Flash Memory	Up to 8 MB
RAM	Up to 1 MB
Operating Voltage	1.62V to 5.5V
Operating Temperature	-40°C to +85°C or +105°C
Package	BGA, LQFP
ADC Resolution	12-bit
DAC Resolution	12-bit
Communication Interfaces	SCI, SPI, I2C, USB, Ethernet, CAN
Architecture	32-bit
Security Features	Memory Protection Unit (MPU)