SH7052 Datasheet, PDF (767/919 Pages) Renesas Technology Corp – SuperHTM RISC engine

User Program Mode
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
SH7054F
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 confirms this fact, executes transfer
program in the flash memory, and transfers the
programming/erase control program to RAM.
Host
New application
program
SH7054F
Boot program
Flash memory
FWE assessment
program
Transfer program
Application program
(old version)
SCI
RAM
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
SH7054F
Boot program
Flash memory
FWE assessment
program
;^{Transfer program}
SCI
RAM
Programming/
erase control program
SH7054F
Boot program
Flash memory
FWE assessment
program
Transfer program
SCI
RAM
Programming/
erase control program
Flash memory
erase
New application
program
Figure 21.4 User Program Mode
Program execution state
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