Figure 17.4 User Program Mode (Example) - Hitachi H8/3062 Hardware Manual

• 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.
Host
Programming/
erase control program
New application
program
H8/3062F-ZTAT or
H8/3062F-ZTAT R-mask version
Boot program
Flash memory
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.
Host
New application
program
H8/3062F-ZTAT or
H8/3062F-ZTAT R-mask version
Boot program
Flash memory
Transfer Program
Flash memory
erase
492
SCI
RAM
SCI
RAM
Programming/
erase control program

Figure 17.4 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
H8/3062F-ZTAT or
H8/3062F-ZTAT R-mask version
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.
Host
H8/3062F-ZTAT or
H8/3062F-ZTAT R-mask version
Boot program
Flash memory
Transfer Program
New application
program
SCI
RAM
Programming/
erase control program
SCI
RAM
Programming/
erase control program
Program execution state