SH7014 Datasheet, PDF (543/754 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

18. 128 kB Flash Memory (F-ZTAT)
18.6.2 User Program Mode
After setting FWP, the user should branch to, and execute, the previously prepared
programming/erase control program.
As the flash memory itself cannot be read while flash memory programming/erasing is being
executed, the control program that performs programming and erasing should be run in on-chip
RAM or external memory.
Use the following procedure (figure 18.12) to execute the programming control program that
writes to flash memory (when transferred to RAM).
Write FWP assessment program
1
and transfer program
2
FWP = 1
(user program mode)
3
Transfer programming/erase
control program to RAM
Execute programming/
4 ^{erase control program in RAM}
(flash memory rewriting)
Execute user application
5
program
Figure 18.12 User Program Mode Execution Procedure
Note: When programming and erasing, start the watchdog timer so that measures can be taken to
prevent program runaway, etc. Memory cells may not operate normally if
overprogrammed or overerased due to program runaway.
Rev.5.00 Sep. 27, 2007 Page 509 of 716
REJ09B0398-0500