HD6412332 RENESAS [Renesas Technology Corp], HD6412332 Datasheet - Page 771

• Manufacturer Part Number: HD6412332
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

19.4.4
• Boot mode
1.
3.
Chip
Chip
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.
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.
On-Board Programming Modes
Application program
Flash memory
Flash memory
Flash memory
prewrite-erase
Boot program
Boot program
(old version)
Programming control
New application
New application
program
program
program
Host
Host
Boot program area
Programming control
program
RAM
RAM
Figure 19.4 Boot Mode
SCI
SCI
2.
4.
Chip
Chip
Programming control program transfer
When boot mode is entered, the boot program in
the 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.
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.
Application program
Rev.4.00 Sep. 07, 2007 Page 741 of 1210
New application
Flash memory
Flash memory
Boot program
Boot program
(old version)
program
New application
program
Host
Host
Boot program area
Boot program area
Programming control
Programming control
Program execution state
program
program
RAM
RAM
REJ09B0245-0400
SCI
SCI