Renesas H8S Series Hardware Manual page 651

• User program mode
1. Initial state
(1) The program that will transfer the
programming/erase control program to on-chip
RAM should be written into the flash memory by
the user beforehand. (2) The programming/erase
control program should be prepared in the host
or in the flash memory.
Chip
Boot program
Flash memory
Transfer program
Application program
3. Flash memory initialization
The programming/erase program in RAM is
executed, and the flash memory is initialized (to
H'FF). Erasing can be performed in block units,
but not in byte units.
Chip
Boot program
Flash memory
Transfer program
Flash memory
Host
Programming/
erase control program
New application
program
RAM
(old version)
Host
New application
program
RAM
Programming/
erase control program
erase
Figure 19-39 User Program Mode (Example)
2. Programming/erase control program transfer
Executes the transfer program in the flash
memory, and transfers the programming/erase
control program to RAM.
Chip
SCI
Boot program
Flash memory
Transfer program
Application program
(old version)
4. Writing new application program
Next, the new application program in the host is
written into the erased flash memory blocks. Do
not write to unerased blocks.
Chip
SCI
Boot program
Flash memory
Transfer program
New application
program
Host
New application
program
SCI
RAM
Programming/
erase control program
Host
SCI
RAM
Programming/
erase control program
Program execution state
Rev.6.00 Oct.28.2004 page 623 of 1016
REJ09B0138-0600H