HD64F3028F25 Datasheet, PDF (640/925 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

18.7 Flash Memory Protection
There are three kinds of flash memory program/erase protection: hardware, software, and error
protection.
18.7.1 Hardware Protection
Hardware protection refers to a state in which programming/erasing of flash memory is forcibly
disabled or aborted. In this state, the settings in flash memory control register 1 (FLMCR1) and
erase block registers 1 and 2 (EBR1, EBR2) are reset. In the error protection state, the FLMCR1,
EBR1, and EBR2 settings are retained; the P bit and E bit can be set, but a transition is not made
to program mode or erase mode. (See table 18.8.)
Table 18.8 Hardware Protection
Function
Item
Description
Program Erase Verify
FWE pin • When a low level is input to the FWE pin,
protection
FLMCR1, EBR1, and EBR2 are initialized, and
the program/erase-protected state is entered.
Not
Not
Not
possible^*1 possible^*3 possible
Reset/
• In a reset (including a WDT overflow reset)
standby
and in standby mode, FLMCR1, FLMCR2,
protection
EBR1, and EBR2 are initialized, and the
program/erase-protected state is entered.
Not
Not
Not
possible possible^*3 possible
Error
protection
• 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.^*4
• When a microcomputer operation error (error Not
generation (FLER = 1)) was detected while flash ^possible
memory was being programmed/erased, error
protection is enabled. At this time, the FLMCR1,
EBR1, and EBR2 settings are held, but
programming/erasing is aborted at the time the
error was generated. Error protection is released
only by a reset via the RES pin or a WDT reset,
or in the hardware standby mode.
Not
Possible^*2
possible^*3
Notes: 1. The RAM area that overlapped flash memory is deleted.
2. It is possible to perform a program-verify operation on the 128 bytes being
programmed, or an erase-verify operation on the block being erased.
Rev. 2.00, 09/03, page 608 of 890