D12320VF25V Datasheet, PDF (768/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 17 ROM
Download and initialization are performed only once at the beginning.
In this kind of operation, note the following:
• Be careful not to damage on-chip RAM with overlapped settings.
In addition to the RAM emulation area, erasing program area, and programming program area,
areas for the user procedure programs, work area, and stack area are reserved in on-chip RAM.
Do not make settings that will overwrite data in these areas.
• Be sure to initialize both the erasing program and programming program.
Initialization by setting the FPEFEQ parameter must be performed for both the erasing
program and the programming program. Initialization must be executed for both entry
addresses: (download start address for erasing program) + 32 bytes (H'FFBC20 in this
example) and (download start address for programming program) + 32 bytes (H'FFCC20 in
this example).
17.24.3 User Boot Mode
This LSI has user boot mode which is initiated with different mode pin settings than those in user
program mode or boot mode. User boot mode is a user-arbitrary boot mode, unlike boot mode that
uses the on-chip SCI.
Only the user MAT can be programmed/erased in user boot mode. Programming/erasing of the
user boot MAT is only enabled in boot mode or programmer mode.
User Boot Mode Initiation: For the mode pin settings to start up user boot mode, see table 17.52.
When the reset start is executed in user boot mode, the built-in check routine runs. The user MAT
and user boot MAT states are checked by this check routine.
While the check routine is running, NMI and all other interrupts cannot be accepted.
Next, processing starts from the execution start address of the reset vector in the user boot MAT.
At this point, H'AA is set to the flash MAT select register FMATS because the execution MAT is
the user boot MAT.
User MAT Programming in User Boot Mode: For programming the user MAT in user boot
mode, additional processings made by setting FMATS are required: switching from user-boot-
MAT selection state to user-MAT selection state, and switching back to user-boot-MAT selection
state after programming completes.
Figure 17.73 shows the procedure for programming the user MAT in user boot mode.
Rev.7.00 Feb. 14, 2007 page 734 of 1108
REJ09B0089-0700