Flash Memory Protection; Hardware Protection - Hitachi H8S/2199 Hardware Manual

7.6

Flash Memory Protection

There are three kinds of flash memory program/erase protection: hardware protection, software
protection, and error protection.
7.6.1

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 flash memory control registers 1
and 2 (FLMCR1, FLMCR2) and erase block registers 1 and 2 (EBR1, EBR2). (See table 7.6.)
In error protected state, the FLMCR1, FLMCR2, EBR1, and EBR2 settings are maintained.
Table 7.6 Hardware Protection
Item Description
• When a low level is input to the FWE pin, FLMCR1,
FWE pin
protection
• In a reset (including a WDT overflow reset) and in
Reset/standby
protection
• In a reset via the 5(6 pin, the reset state is not
FLMCR2 (excluding the FLER bit), EBR1, and EBR2
are initialized, and the program/erase-protected state
is entered
standby mode, FLMCR1, FLMCR2, EBR1, and EBR2
are initialized, and the program/erase-protected state
is entered
entered unless the 5(6 pin is held low until oscillation
stabilizes after powering on. In the case of a reset
during operation, hold the 5(6 pin low for the 5(6
pulse width specified in the AC characteristics
Functions
Program
Yes
Yes
Rev. 1.0, 02/00, page 153 of 1141
Erase
Yes
Yes