D12320VF25IV Datasheet, PDF (855/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 19 ROM
Table 19.33 Software Protection
Functions
Item
Description
Program Erase
SWE bit protection • Clearing the SWE bit to 0 in FLMCR1 sets the Yes
Yes
program/erase-protected state for all blocks
• (Execute in on-chip RAM or external memory.)
Block specification • Erase protection can be set for individual
—
Yes
protection
blocks by settings in erase block registers 1
and 2 (EBR1, EBR2).
• Setting EBR1 and EBR2 to H'00 places all
blocks in the erase-protected state.
Emulation protection • Setting the RAMS bit to 1 in the RAM emulation Yes
Yes
register (RAMER) places all blocks in the
program/erase-protected state.
19.17.3 Error Protection
In error protection, an error is detected when MCU runaway occurs during flash memory
programming/erasing, or operation is not performed in accordance with the program/erase
algorithm, and the program/erase operation is aborted. Aborting the program/erase operation
prevents damage to the flash memory due to overprogramming or overerasing.
If the MCU malfunctions during flash memory programming/erasing, the FLER bit is set to 1 in
FLMCR2 and the error protection state is entered. The FLMCR1, FLMCR2, EBR1, and EBR2
settings are retained, but program mode or erase mode is aborted at the point at which the error
occurred. Program mode or erase mode cannot be re-entered by re-setting the P or E bit. However,
PV and EV bit setting is enabled, and a transition can be made to verify mode.
FLER bit setting conditions are as follows:
• When flash memory is read during programming/erasing (including a vector read or instruction
fetch)
• Immediately after exception handling (excluding a reset) during programming/erasing
• When a SLEEP instruction (including software standby) is executed during
programming/erasing
• When a bus master other than the CPU (the DMAC or DTC) has control of the bus during
programming/erasing
Rev.6.00 Sep. 27, 2007 Page 823 of 1268
REJ09B0220-0600