UPD70F3786GJ-GAE-AX Datasheet, PDF (1681/1817 Pages) Renesas Technology Corp – RENESAS MCU V850ES/Jx3-E Microcontrollers

V850ES/JH3-E, V850ES/JJ3-E
CHAPTER 33 FLASH MEMORY
33.5.2 Features
(1) Secure self programming (boot swap function)
The V850ES/JH3-E and V850ES/JJ3-E support a boot swap function that can exchange the physical memory of
blocks 0 to 15 with the physical memory of blocks 16 to 31. By writing the start program to be rewritten to blocks
16 to 31 in advance and then swapping the physical memory, the entire area can be safely rewritten even if a
power failure occurs during rewriting because the correct user program always exists in blocks 0 to 15.
Figure 33-17. Rewriting Entire Memory Area (Boot Swap)
Last block
:
Block 32
Block 31
:
Block 17
Block 16
Block 15
:
Block 1
Block 0
Rewriting blocks
16 to 31
Last block
:
Block 32
Block 31
:
Block 17
Block 16
Block 15
:
Block 1
Block 0
Boot swap
Last block
:
Block 32
Block 31
:
Block 17
Block 16
Block 15
:
Block 1
Block 0
(2) Interrupt support
Instructions cannot be fetched from the flash memory during self-programming. Consequently, a user handler
written to the flash memory could not be used even if an interrupt has occurred.
Therefore, in the V850ES/JH3-E and V850ES/JJ3-E, to use an interrupt during self-programming, processing
transits to the specific address^Note in the internal RAM. Allocate the jump instruction that transits processing to the
user interrupt servicing at the specific address^Note in the internal RAM.
Note NMI interrupt:
Start address of internal RAM
Maskable interrupt: Start address of internal RAM + 4 addresses
R01UH0290EJ0300 Rev.3.00
Sep 19, 2011
Page 1681 of 1817