HD6432621 Hitachi, HD6432621 Datasheet - Page 663

• Manufacturer Part Number: HD6432621
• Description: (HD64F262x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

User Program Mode
1. Initial state
3. Flash memory initialization
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.
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.
LSI
LSI
Application program
Transfer program
Transfer program
FWE assessment
FWE assessment
Flash memory
Flash memory
Flash memory
Boot program
Boot program
(old version)
program
program
erase
erase control program
New application
New application
Programming/
program
program
Host
Host
erase control program
Programming/
RAM
RAM
SCI
SCI
2. Programming/erase control program transfer
4. Writing new application program
LSI
LSI
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.
Next, the new application program in the host is
written into the erased flash memory blocks. Do
not write to unerased blocks.
Application program
Transfer program
New application
FWE assessment
FWE assessment
Transfer program
Flash memory
Flash memory
Boot program
Boot program
(old version)
program
program
program
New application
program
Host
Host
erase control program
erase control program
Programming/
Programming/
Program execution state
RAM
RAM
SCI
SCI
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