Datasheet

Section 20 Flash Memory (0.18-μm F-ZTAT Version)
Rev.6.00 Mar. 18, 2009 Page 778 of 980
REJ09B0050-0600
20.5 Protection
There are two kinds of flash memory program/erase protection: hardware and software protection.
20.5.1 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 20.9 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.