HD6432646 Hitachi, HD6432646 Datasheet - Page 723

• Manufacturer Part Number: HD6432646
• Description: (HD64F264x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

20.8
There are three kinds of flash memory program/erase protection: hardware protection, software
protection, and error protection.
20.8.1
Hardware protection refers to a state in which programming/erasing of flash memory is forcibly
disabled or aborted. Hardware protection is reset by settings in flash memory control register 1
(FLMCR1), flash memory control register 2 (FLMCR2), erase block register 1 (EBR1), and erase
block register 2 (EBR2). The FLMCR1, FLMCR2, EBR1, and EBR2 settings are retained in the
error-protected state. (See table 20-7.)
Table 20-7 Hardware Protection
Item
FWE pin protection
Reset/standby
protection
Protection
Hardware Protection
Description
When a low level is input to the FWE pin,
FLMCR1, FLMCR2, (except bit FLER)
EBR1, and EBR2 are initialized, and the
program/erase-protected state is entered.
In a reset (including a WDT reset) and in
standby mode, FLMCR1, FLMCR2, EBR1,
and EBR2 are initialized, and the
program/erase-protected state is entered.
In a reset via the RES pin, the reset state
is not entered unless the RES pin is held
low until oscillation stabilizes after
powering on. In the case of a reset during
operation, hold the RES pin low for the
RES pulse width specified in the AC
Characteristics section.
Program
Yes
Yes
Functions
Erase
Yes
Yes
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