Rev. 1.0, 02/00, page 128 of 1141
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User program mode
<Flash memory>
<This LSI>
<RAM>
<Host>
Programming/erase control program
SCI
Boot program
New application
program
<This LSI>
<RAM>
<Host>
SCI
<Flash memory>
<This LSI>
<RAM>
<Host>
SCI
Flash memory erase
Boot program
New application
program
<This LSI>
Program execution state
<RAM>
<Host>
SCI
Programming/erase
control program
1. Initial state
2. Programming/erase control program transfer
3. Flash memory initialization
4. Writing new application program
FWE assessment program
Transfer program
Application
program
(old version)
,
FWE assessment program
Transfer program
Programming/erase control program
Programming/erase control program
<Flash memory>
New application
program
Boot program
FWE assessment program
Transfer program
(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.
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.
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.
Next, the new application program in the host is written
into the erased flash memory blocks. Do not write to
unerased blocks.
New application
program
<Flash memory>
Boot program
FWE assessment program
Transfer program
Application
program
(old version)
Figure 7.5 User Program Mode (Example)