D12320VF25IV Datasheet, PDF (821/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 19 ROM
19.11.10 Notes on Memory Programming
• When programming addresses which have previously been programmed, carry out auto-
erasing before auto-programming.
• When performing programming using PROM mode on a chip that has been
programmed/erased in an on-board programming mode, auto-erasing is recommended before
carrying out auto-programming.
Notes: 1. The flash memory is initially in the erased state when the device is shipped by Renesas
Technology. For other chips for which the erasure history is unknown, it is
recommended that auto-erasing be executed to check and supplement the initialization
(erase) level.
2. Auto-programming should be performed once only on the same address block.
Additional programming cannot be carried out on address blocks that have already
been programmed.
19.12 Flash Memory Programming and Erasing Precautions
Precautions concerning the use of on-board programming mode, the RAM emulation function, and
PROM mode are summarized below.
Use the specified voltages and timing for programming and erasing: Applied voltages in
excess of the rating can permanently damage the device. Use a PROM programmer that supports
the Renesas microcomputer device type with 512-kbyte on-chip flash memory (FZTAT512V3A).
Do not select the HN27C4096 setting for the PROM programmer, and only use the specified
socket adapter. Failure to observe these points may result in damage to the device.
Powering on and off: When applying or disconnecting V_CC power, fix the RES pin low and place
the flash memory in the hardware protection state.
The power-on and power-off timing requirements should also be satisfied in the event of a power
failure and subsequent recovery.
Use the recommended algorithm when programming and erasing flash memory: The
recommended algorithm enables programming and erasing to be carried out without subjecting the
device to voltage stress or sacrificing program data reliability. When setting the P or E bit in
FLMCR1, the watchdog timer should be set beforehand as a precaution against program runaway,
etc.
Rev.6.00 Sep. 27, 2007 Page 789 of 1268
REJ09B0220-0600