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*3 All blocks are unerasable and block-by-block specification is not possible.
*4 See section 4.2.2, Reset Sequence, and section 18.11, Flash Memory Programming
and Erasing Precautions. The H8/3064F-ZTAT B-mask version requires a minimum of
20 system clock cycles for a reset during operation.
18.7.2
Software Protection
Software protection can be implemented by setting the erase block register 1 (EBR1), erase block
register 2 (EBR2), and the RAMS bit in the RAM control register (RAMCR). With software
protection, setting the P or E bit in the flash memory control register 1 (FLMCR1) does not cause
a transition to program mode or erase mode (See table 18.10).
Table 18.10
Software Protection
Item
Description
•
Block
Erase protection can be set for individual
protection
blocks by settings in erase block register 1
(EBR1) and erase block register 2
(EBR2) *
protection is disabled.
• Setting EBR1 and EBR2 to H'00 places all
blocks in the erase-protected state.
•
Emulation
Setting the RAMS bit 1 in RAMCR places
protection
all blocks in the program/erase-protected
state.
Notes: *1 The RAM area overlapping flash memory can be written to.
*2 When not erasing, set EBR1 and EBR2 to H'00.
*3 All blocks are unerasable and block-by-block specification is not possible.
18.7.3
Error Protection
In error protection, an error is detected when MCU runaway occurs during flash memory
programming/erasing *
algorithm, and the program/erase operation is aborted. Aborting the program/erase operation
prevents damage to the flash memory due to overprogramming or overerasing.
If the MCU malfunctions during flash memory programming/erasing, the FLER bit is set to 1 in
the flash memory status register (FLMSR2) and the error protection state is entered. FLMCR1,
FLMCR2, EBR1, and EBR2 settings *
the point at which the error occurred. Program mode or erase mode cannot be re-entered by re-
2
. However, programming
1
, or operation is not performed in accordance with the program/erase
3
are retained, but program mode or erase mode is aborted at
Functions
Program
Erase
—
Not
possible
Not
Not
1
possible *
possible *
Verify
Possible
Possible
3
559
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