Renesas Hitachi H8S/2194 Series Hardware Manual page 155

(b) 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 from the flash memory 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.
<Host>
Programming/erase control program
New application
program
<This LSI>
Boot program
<Flash memory>
FWE assessment program
Transfer program
Application
program
(old version)
3. Flash memory initialization
The programming/erase control 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
<This LSI>
Boot program
<Flash memory>
FWE assessment program
Transfer program
Flash memory erase
Rev. 2.0, 11/00, page 128 of 1037
SCI
<RAM>
SCI
<RAM>
Programming/erase control program
Figure 7.5 User Program Mode (Example)
2. Programming/erase control program transfer
When user program mode is entered, 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
<This LSI>
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>
<This LSI>
Boot program
<Flash memory>
FWE assessment program
Transfer program
New application
program
SCI
<RAM>
Programming/erase
control program
SCI
<RAM>
Programming/erase control program
Program execution state