HD64F3048VTF8 Datasheet, PDF (607/903 Pages) Renesas Technology Corp – Hardware Manual Renesas 8-Bit Single-Chip

Section 18 ROM (H8/3048F-ONE: Single Power Supply, H8/3048B Mask ROM Version)
18.2.3 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
H8/3048F-ONE
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 H8/3048F-ONE (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
H8/3048F-ONE
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, total flash
memory erasure is performed, without regard to
blocks.
Host
New application
program
H8/3048F-ONE
Boot program
Flash memory
SCI
RAM
Flash memory
preprogramming
erase
Boot program area
Programming control
program
4. Writing new application program
The programming control program is recognized
if it corresponds to the H8/3048F-ONE.
The programming control program is then
transferred from the host to RAM is executed,
and the new application program in the host is
written into the flash memory.
Host
H8/3048F-ONE
Boot program
Flash memory
New application
program
SCI
RAM
Boot program area
Programming control
program
Note: Never apply 12 V to the H8/3048F-ONE (single power supply).
Otherwise, the LSI will be permanently damaged.
Program execution state
Rev. 3.00 Sep 27, 2006 page 579 of 872
REJ09B0325-0300