D12320VF25V Datasheet, PDF (723/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 17 ROM
17.22.3 Operating Mode of Flash Memory
When each mode pin is set in the reset state and reset start is performed, the microcomputer enters
each operating mode as shown in figure 17.61. For the setting of each mode pin, see table 17.52.
• Flash memory cannot be read, programmed, or erased in ROM invalid mode.
• Flash memory can be read in user mode, but cannot be programmed or erased.
• Flash memory can be read, programmed, or erased on the board only in user program mode,
user boot mode, and boot mode.
• Flash memory can be read, programmed, or erased by means of the PROM programmer in
PROM mode.
ROM invalid
mode
RES=0
ROM invalid
mode setting
Reset state
RES=0
PROM mode setting
PROM mode
R_U^E_s^S_er⁼_m⁰_ode sett^ing
B_oot
RES₌₀
mode _setting
User mode
FLSHE=0
User program
FLSHE=1
mode
User boot
mode
RAM emulation is enabled
On-board programming mode
Boot mode
Figure 17.61 Mode Transition of Flash Memory
Rev.7.00 Feb. 14, 2007 page 689 of 1108
REJ09B0089-0700