r5f71374an80fpv Renesas Electronics Corporation., r5f71374an80fpv Datasheet - Page 924

• Manufacturer Part Number: r5f71374an80fpv
• Description: 32-bit Risc Microcomputer Superh?? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

Section 22 Flash Memory
(4) Flash Key Code Register (FKEY)
Rev. 1.00 Sep. 21, 2007 Page 898 of 1124
REJ09B0402-0100
Bit
0
Bit
7 to 0
FKEY is a register for software protection that enables download of the on-chip program and
programming/erasing of flash memory. Before setting the SCO bit to 1 in order to download
the on-chip program or executing the downloaded programming/erasing program, these
processing cannot be executed if the key code is not written.
Bit Name
EPVB
Bit Name
K[7:0]
Initial
Value
0
Initial
Value
All 0
Initial value:
R/W:
Bit:
R/W
R/W
R/W
R/W
R/W
7
0
R/W
6
0
Description
Erase Pulse Verify Block
Selects the erasing program.
0: On-chip erasing program is not selected
[Clearing condition]
When transfer is completed
1: On-chip erasing program is selected
Description
Key Code
Only when H'A5 is written, writing to the SCO bit is valid.
When a value other than H'A5 is written to FKEY, 1
cannot be written to the SCO bit. Therefore downloading
to the on-chip RAM cannot be executed.
Only when H'5A is written, programming/erasing of flash
memory can be executed. Even if the on-chip
programming/erasing program is executed, flash memory
cannot be programmed or erased when a value other than
H'5A is written to FKEY.
H'A5: Writing to the SCO bit is enabled (The SCO bit
H'5A: Programming/erasing is enabled (A value other than
H'00: Initial value
R/W
5
0
cannot be set by a value other than H'A5.)
H'5A enables software protection state.)
R/W
4
0
K[7:0]
R/W
3
0
R/W
2
0
R/W
1
0
R/W
0
0