HD6432633 Datasheet, PDF (947/1453 Pages) Renesas Technology Corp – Series of Microcomputers (MCUs: microcomputer units)

21.3 Operation
When the RAME bit is set to 1, accesses to addresses H'FFB000 to H'FFEFBF and H'FFFFC0 to
H'FFFFFF in the H8S/2633 and H8S/2633R, to addresses H'FFC000 to H'FFEFBF and H'FFFFC0
to H'FFFFFF in the H8S/2632, and to addresses H'FFD000 to H'FFEFBF and H'FFFFC0 to
H'FFFFFF in the H8S/2631 and H8S/2695, are directed to the on-chip RAM. When the RAME bit
is cleared to 0, the off-chip address space is accessed.
Since the on-chip RAM is connected to the CPU by an internal 16-bit data bus, it can be written to
and read in byte or word units. Each type of access can be performed in one state.
Even addresses use the upper 8 bits, and odd addresses use the lower 8 bits. Word data must start
at an even address.
21.4 Usage Notes
When Using the DTC*: DTC* register information can be located in addresses H'FFEBC0 to
H'FFEFBF. When the DTC* is used, the RAME bit must not be cleared to 0.
Note: * The DTC function is not available in the H8S/2695.
Reserved Areas: Addresses H'FFB000 to H'FFBFFF in the H8S/2632, and H'FFB000 to
H'FFCFFF in the H8S/2631 and H8S/2695 are reserved areas that cannot be read or written to.
When the RAME bit is cleared to 0, the off-chip address space is accessed.
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