D12320VF25IV Datasheet, PDF (848/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 19 ROM
Write the FWE assessment program and
transfer program (and the program/erase
control program if necessary) beforehand
MD2, MD1, MD0 = 110, 111
Reset-start
Transfer program/erase control
program to RAM
Branch to program/erase control
program in RAM area
FWE = high*
Execute program/erase control
program (flash memory rewriting)
Clear FWE*
Branch to flash memory application
program
Notes: Do not apply a constant high level to the FWE pin. Apply a high level to the FWE pin
only when the flash memory is programmed or erased. Also, while a high level is
applied to the FWE pin, the watchdog timer should be activated to prevent
overprogramming or overerasing due to program runaway, etc.
* For further information on FWE application and disconnection, see section 19.21,
Flash Memory Programming and Erasing Precautions.
Figure 19.40 User Program Mode Execution Procedure
Rev.6.00 Sep. 27, 2007 Page 816 of 1268
REJ09B0220-0600