Renesas H8S/2319 series Hardware Manual page 591

• User program mode
1. Initial state
(1) The FWE assessment program that confirms
that the FWE pin has been driven high, and (2)
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. (3) The programming/erase control
program should be prepared in the host or in the
flash memory.
Programming/
erase control program
New application
program
Chip
Boot program
Flash memory
FWE assessment
program
Transfer program
Application program
(old version)
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.
New application
program
Chip
Boot program
Flash memory
FWE assessment
program
Transfer program
Flash memory
erase
Host
SCI
RAM
Host
SCI
RAM
Programming/
erase control program
Figure 17-5 User Program Mode (Example)
2. Programming/erase control program transfer
When the FWE pin is driven high, user software
confirms this fact, executes the transfer program
in the flash memory, and transfers the
programming/erase control program to RAM.
Host
New application
program
Chip
Boot program
Flash memory
FWE assessment
program
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.
Host
Chip
Boot program
Flash memory
FWE assessment
program
Transfer program
New application
program
Rev. 5.00, 12/03, page 561 of 1088
SCI
RAM
Programming/
erase control program
SCI
RAM
Programming/
erase control program
Program execution state