SH7080_09 Datasheet, PDF (1292/1622 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family

Section 23 Flash Memory
Initial
Bit
Bit Name Value R/W Description
0
EPVB
0
R/W 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
(4) Flash Key Code Register (FKEY)
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
processings cannot be executed if the key code is not written.
Bit: 7
6
5
4
3
2
1
0
K[7:0]
Initial value: 0
0
0
0
0
0
0
0
R/W: R/W R/W R/W R/W R/W R/W R/W R/W
Initial
Bit
Bit Name Value R/W
7 to 0 K[7:0]
All 0 R/W
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
cannot be set by a value other than H'A5.)
H'5A: Programming/erasing is enabled (A value other than
H'5A enables software protection state.)
H'00: Initial value
Rev. 4.00 Dec. 15, 2009 Page 1232 of 1558
REJ09B0181-0400