NEC 78K0 Series User Manual page 575

The procedure of self-programming is illustrated below.
Interrupt request
Interrupt servicing
CHAPTER 26 FLASH MEMORY
Figure 26-16. Self-Programming Procedure
Start self-programming
Secure entry RAM area
Set parameters
to entry RAM
FLMD0 pin = High level
Execute DI instruction
Execute library and access
flash memory according
to library contents
Execute EI instruction
No interrupt request
Confirm library return value
FLMD0 pin = Low level
End of self-programming
Preliminary User's Manual U17260EJ3V1UD
Entry program
(user program)
Library
Entry program
(user program)
Self-programming
being suspended
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