HD64F3028F25 Datasheet, PDF (617/925 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

*1
User mode
with on-chip ROM
enabled
FWE = 0
*4
*3
Reset state
RES = 0
*4
RES = 0
RES = 0
*2
*5 _{RES = 0}
PROM mode
User program ^*1
mode
On-board programming mode
Boot mode
Notes: Only make a transition between user mode and user program mode when the CPU is not
accessing the flash memory.
1. RAM emulation possible
2. The H8/3028F-ZTAT is placed in PROM mode by means of a dedicated PROM writer.
3. MD₂, MD₁, MD₀ = (1, 0, 1) (1, 1, 0) (1, 1, 1)
FWE = 0
4. MD₂, MD₁, MD₀ = (1, 0, 1) (1, 1, 1)
FWE = 1
5. MD₂, MD₁, MD₀ (0, 0, 1) (0, 1, 1)
FWE = 1
Figure 18.2 Flash Memory Related State Transitions
State transitions between the normal and user modes and on-board programming mode are
performed by changing the FWE pin level from high to low or from low to high. To prevent
misoperation (erroneous programming or erasing) in these cases, the bits in the flash memory
control register (FLMCR1) should be cleared to 0 before making such a transition. After the bits
are cleared, a wait time is necessary. Normal operation is not guaranteed if this wait time is
insufficient.
Rev. 2.00, 09/03, page 585 of 890