Datasheet

Section 22 ROM (Mask ROM Version, H8S/2148 F-ZTAT, H8S/2147N F-ZTAT, H8S/2144 F-ZTAT, and H8S/2142 F-ZTAT)
Rev. 4.00 Sep 27, 2006 page 683 of 1130
REJ09B0327-0400
22.10.10 Notes on Memory Programming
• When programming addresses which have previously been programmed, carry out auto-
erasing before auto-programming.
• When performing programming using programmer 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.
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.
22.11 Flash Memory Programming and Erasing Precautions
Precautions concerning the use of on-board programming mode and programmer 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. For a PROM
programmer, use Renesas Technology microcomputer device types with 128-kbyte or 64-kbyte
on-chip flash memory that support a 5.0-V programming voltage.
Do not select the HN28F101 or use a programming voltage of 3.3 V for the PROM programmer,
and only use the specified socket adapter. Incorrect use will result in damaging the device.
Powering on and off
When applying or disconnecting V
CC
, 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.
Do not set or clear the SWE bit during program execution in flash memory.
Clear the SWE bit before executing a program or reading data in flash memory. When the SWE
bit is set, data in flash memory can be rewritten, but flash memory should only be accessed for
verify operations (verification during programming/erasing).