Renesas H8S/2318 series, Руководство по оборудованию

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Rev. 5.00, 12/03, page 678 of 1088
(3) Flash Erase Code Select Register (FECS)
FECS selects download of the on-chip erasing program.
Bit : 7 6 5 4 3 2 1 0
— — — — — — — EPVB
Initial value : 0 0 0 0 0 0 0 0
R/W : R R R R R R R R/W
Bits 7 to 1—Reserved: These bits are always read as 0. The write value should always be 0.
Bit 0—Erase Pulse Verify Block (EPVB): Selects the erasing program.
Bit 0
EPVB Description
0 On-chip erasing program is not selected (Initial value)
[Clear 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 on-chip program and
programming/erasing of flash memory. Before setting the SCO bit to 1 in order to download on-
chip program or executing the downloaded programming/erasing program, these processing
cannot be executed if the key code is not written.
Bit : 7 6 5 4 3 2 1 0
K7 K6 K5 K4 K3 K2 K1 K0
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
Bits 7 to 0—Key Code (K7 to K0): Only when H'A5 is written, writing to the SCO bit is valid.
When the 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 can be executed. Even if the on-chip
programming/erasing program is executed, flash memory cannot be programmed or erased when
the value other than H'5A is written to FKEY.