Datasheet

Section 21 Flash Memory (0.18-μm F-ZTAT Version)
Rev.7.00 Mar. 18, 2009 page 920 of 1136
REJ09B0109-0700
21.5 Protection
There are two kinds of flash memory program/erase protection: hardware and software protection.
21.5.1 Hardware Protection
Programming and erasing of flash memory is forcibly disabled or suspended by hardware
protection. In this state, the downloading of a on-chip program and initialization are possible.
However, an activated program for programming or erasure cannot program or erase locations in a
user MAT, and the error in programming/erasing is reported in the parameter FPFR.
Table 21.9 Hardware Protection
Function to be Protected
Item Description Download Program/Erase
Reset/standby
protection
• The program/erase interface
registers are initialized in the power-
on reset state (including a power-on
reset by the WDT) and standby
mode and the program/erase-
protected state is entered.
• The reset state will not be entered by
a reset using the RES pin unless the
RES pin is held low until oscillation
has stabilized after power is initially
supplied. In the case of a reset
during operation, hold the RES pin
low for the RES pulse width that is
specified in the section on AC
characteristics section. If a reset is
input during programming or
erasure, data values in the flash
memory are not guaranteed. In this
case, execute erasure and then
execute program again.