HD64F3048VTF8 Datasheet, PDF (649/903 Pages) Renesas Technology Corp – Hardware Manual Renesas 8-Bit Single-Chip

Section 18 ROM (H8/3048F-ONE: Single Power Supply, H8/3048B Mask ROM Version)
Similarly perform flash memory program execution and data read after clearing the SWE bit
even when using the RAM emulation function with a high level input to the FWE pin.
However, RAM area that overlaps flash memory space can be read/programmed whether the
SWE bit is set or cleared.
After the SWE bit is cleared, waiting time is required. For details, refer to table 21.11 in
section 21.1.6, Flash Memory Characteristics.
7. Do not use an interrupt during flash memory programming or erasing.
Since programming/erase operations (including emulation by RAM) have priority when a high
level is input to the FWE pin, disable all interrupt requests, including NMI. The bus release
should also be disabled.
8. Do not perform additional programming. Reprogram flash memory after erasing.
With on-board programming, program to 128-byte programming unit blocks one time only.
Erase all the programming unit blocks before reprogramming.
9. Before programming, check that the chip is correctly mounted in the PROM
programmer.
Overcurrent damage to the device can result if the index marks on the PROM programmer
socket, socket adapter, and chip are not correctly aligned.
10. Do not touch the socket adapter or chip during programming.
Touching either of these can cause contact faults and write errors.
11. A wait time of 100 µs or more is necessary when performing a read after a transition to
normal mode from program, erase, or verify mode.
12. Use byte access on the registers that control the flash memory (FLMCR1, FLMCR2,
EBR, and RAMCR).
Rev. 3.00 Sep 27, 2006 page 621 of 872
REJ09B0325-0300