UPD784218 Datasheet, PDF (22/92 Pages) NEC – 16-/8-BIT SINGLE-CHIP MICROCONTROLLERS

µPD784218, 784218Y
7. CPU ARCHITECTURE
7.1 Memory Space
A memory space of 1 MB can be accessed. Mapping of the internal data area (special function registers and
internal RAM) can be specified by the LOCATION instruction. The LOCATION instruction must always be executed
after reset cancellation, and must not be used more than once.
(1) When LOCATION 0H instruction is executed
• Internal memory
The internal data area and internal ROM area are mapped as follows:
Part Number
µPD784218,
µPD784218Y
Internal Data Area
0CD00H to 0FFFFH
Internal ROM Area
00000H to 0CCFFH
10000H to 3FFFFH
Caution The following areas that overlap the internal data area of the internal ROM cannot be used when
the LOCATION 0 instruction is executed.
Part Number
µPD784218,
µPD784218Y
Unusable Area
0CD00H to 0FFFFH (13,056 bytes)
• External memory
The external memory is accessed in external memory expansion mode.
(2) When LOCATION 0FH instruction is executed
• Internal memory
The internal data area and internal ROM area are mapped as follows:
Part Number
µPD784218,
µPD784218Y
Internal Data Area
FCD00H to FFFFFH
Internal ROM Area
00000H to 3FFFFH
• External memory
The external memory is accessed in external memory expansion mode.
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Data Sheet U12304EJ2V0DS00