H83062 Datasheet, PDF (570/1021 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 17 ROM [H8/3062F-ZTAT R-Mask Version, On-Chip Masked ROM Models]
Notes: 1. Do not apply a constant high level to the FWE pin. To prevent inadvertent
programming or erasing due to program runaway, etc., apply a high level to the FWE
pin only when the flash memory is programmed or erased (including execution of flash
memory emulation using RAM). Memory cells may not operate normally if
overprogrammed or overerased due to program runaway, etc. 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.
2. Flash memory rewriting should not be carried out in mode 6. When mode 6 is set, the
FWE pin must be driven low.
17.5 Flash Memory Programming/Erasing
A software method, using the CPU, is employed to program and erase flash memory in the on-
board programming modes. There are four flash memory operating modes: program mode, erase
mode, program-verify mode, and erase-verify mode. Transitions to these modes are made by
setting the PSU, ESU, P, E, PV, and EV bits in FLMCR.
The state transitions made by the various FLMCR bit settings are shown in figure 17.10. The flash
memory cannot be read while being programmed or erased. Therefore, the program (user
program) that controls flash memory programming/erasing should be located and executed in on-
chip RAM or external memory.
See section 17.9, Flash Memory Programming and Erasing Precautions, for points to note
concerning programming and erasing, and section 22.2.6, Flash Memory Characteristics, for the
wait times after setting or clearing FLMCR bits.
Notes: 1. Operation is not guaranteed if setting/clearing of the SWE, ESU, PSU, EV, PV, E, and
P bits in FLMCR is executed by a program in flash memory.
2. When programming or erasing, set the FWE pin input level to the high level, and set
FWE to 1 (programming/erasing will not be executed if FWE = 0).
Rev. 6.00 Mar 18, 2005 page 522 of 970
REJ09B0215-0600