HD6475348R Datasheet, PDF (315/487 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

16.3.2 Single-Chip Mode (Mode 7)
If the RAME bit is set to 1, accesses to addresses H'F680 to H'FE7F are directed to the on-chip
RAM. If the RAME bit is cleared to 0, access of any type (instruction fetch or data read or write)
to addresses H'F680 to H'FE7F causes an address error and initiates the CPU’s exception-handling
sequence.
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