HD64F3039F18 Datasheet, PDF (478/710 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8 Family / H8/300H Series

Section 15 ROM
• 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.
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
Programming/
erase control program
New application
program
This chip
Boot program
Flash memory
Transfer
program
SCI
RAM
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
Host
New application
program
This chip
Boot program
Flash memory
Transfer
program
Application program
(old version)
SCI
RAM
Programming/
erase control program
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
This chip
Boot program
Flash memory
FWE assessment
program
Transfer program
Flash memory
erase
SCI
RAM
Programming/
erase control program
This chip
Boot program
Flash memory
FWE assessment
program
Transfer program
New application
program
SCI
RAM
Programming/
erase control program
Program execution state
Figure 15.4 User Program Mode (Example)
Rev.3.00 Mar. 26, 2007 Page 454 of 682
REJ09B0353-0300