UPD784020 Datasheet, PDF (18/90 Pages) NEC – 16/8-BIT SINGLE-CHIP MICROCOMPUTER

mPD784020, 784021
7. CPU ARCHITECTURE
7.1 MEMORY SPACE
A 1M-byte memory space can be accessed. By using a LOCATION instruction, the mode for mapping internal
data areas (special function registers and internal RAM) can be selected. A LOCATION instruction must always be
executed after a reset, and can be used only once.
(1) When the LOCATION 0 instruction is executed
Internal data areas are mapped to 0FD00H-0FFFFH for themPD784020 and 0F700H-0FFFFH for themPD784021.
(2) When the LOCATION 0FH instruction is executed
Internal data areas are mapped to FFD00H-FFFFFH for themPD784020 and FF700H-FFFFFH for themPD784021.
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