Flash Memory Protection; Hardware Protection; Table 17.8 Hardware Protection - Hitachi H8/3062 Hardware Manual

17.6

Flash Memory Protection

There are three kinds of flash memory program/erase protection: hardware, software, and error
protection.
17.6.1

Hardware Protection

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 the flash memory control register
(FLMCR) and the erase block register (EBR). In the case of error protection, the P bit and E bit
can be set, but a transition is not made to program mode or erase mode (See table 17.8).

Table 17.8 Hardware Protection

Item Description
FWE pin protection •
•
Reset/standby
protection
•
506
When a low level is input to the FWE pin,
FLMCR and EBR are initialized, and the
program/erase-protected state is
4
entered *
.
In a reset (including a WDT overflow
reset) and in standby mode, FLMCR and
EBR 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 (The minimum oscillation
stabilization time is 20ms). In the case of
a reset during operation, hold the RES
pin low for at least 20 system clock
5
cycles *
.
Function
Program Erase
Not Not
2 3
possible * possible *
Not Not
3
possible *
possible
1
Verify *
Not
possible
Not
possible