HD64F3028F25 Datasheet, PDF (619/925 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Example of User Program Mode Operation
1. Initial state
The FWE assessment program that confirms
that user program mode has been entered, and
the program that will transfer the programming/
erase control program from flash memory to
on-chip RAM should be written into the flash
memory by the user beforehand. The
programming/erase control program should be
prepared in the host or in the flash memory.
Host
Programming/erase
control program
New application
program
H8/3028F-ZTAT
Boot program
Flash memory
FWE assessment program
Transfer program
SCI
RAM
Application program
(old version)
2. Programming/erase control program transfer
When user program mode is entered, user
software recognizes this fact, executes the
transfer program in the flash memory, and
transfers the programming/erase control
program to RAM.
Host
New application
program
H8/3028F-ZTAT
Boot program
Flash memory
FWE assessment program
Transfer program
SCI
RAM
Application program
(old version)
Programming/erase
control 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.
Host
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.
Host
New application
program
H8/3028F-ZTAT
Boot program
Flash memory
FWE assessment program
Transfer program
SCI
RAM
Flash memory
erase
Programming/erase
control program
H8/3028F-ZTAT
Boot program
Flash memory
FWE assessment program
Transfer program
New application
program
SCI
RAM
Programming/erase
control program
Program execution state
Rev. 2.00, 09/03, page 587 of 890