HD64F2357VF13 Datasheet, PDF (607/1049 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

On-Board Programming Modes
• Boot mode
1. Initial state
The old program version or data remains written
in the flash memory. The user should prepare the
programming control program and new
application program beforehand in the host.
Host
Programming control
program
New application
program
H8S/2357 Group chip
Boot program
Flash memory
SCI
RAM
Application program
(old version)
2. Programming control program transfer
When boot mode is entered, the boot program in
the H8S/2357 chip (originally incorporated in the
chip) is started and the programming control
program in the host is transferred to RAM via SCI
communication. The boot program required for
flash memory erasing is automatically transferred
to the RAM boot program area.
Host
New application
program
H8S/2357 Group chip
Boot program
Flash memory
SCI
RAM
Application program
(old version)
Boot program area
Programming control
program
3. Flash memory initialization
The erase program in the boot program area (in
RAM) is executed, and the flash memory is
initialized (to H'FF). In boot mode, entire flash
memory erasure is performed, without regard to
blocks.
Host
New application
program
 !H8S/2357Groupchip
Boot program
Flash memory
SCI
RAM
Flash memory
erase
Boot program area
Programming control
program
4. Writing new application program
The programming control program transferred
from the host to RAM is executed, and the new
application program in the host is written into the
flash memory.
Host
H8S/2357 Group chip
Boot program
Flash memory
New application
program
SCI
RAM
Boot program area
Programming control
program
",
!^{Figure 19-9 Boot Mode}
Program execution state
Rev.6.00 Oct.28.2004 page 577 of 1016
REJ09B0138-0600H