User Boot Mode - Renesas H8S Series Hardware Manual

In the above procedure, 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 erasing program area and programming program area, areas for the user
procedure programs, work area, and stack area are allocated in the 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 programming program. Initialization must be executed for both entry addresses:
(download start address for erasing program) + 32 bytes and (download start address for
programming program) + 32 bytes.
21.4.3

User Boot Mode

This LSI has user boot mode that is initiated with different mode pin settings than those in boot
mode or user program 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.
(1) User Boot Mode Initiation
For the mode pin settings to start up user boot mode, see table 21.5.
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 FMATS because the execution target MAT is the user boot MAT.
Section 21 Flash Memory (0.18-µm F-ZTAT Version)
Rev. 3.00 Jul. 14, 2005 Page 779 of 986
REJ09B0098-0300