CHAPTER 3 CPU ARCHITECTURE
User’s Manual U18172EJ2V0UD
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3.1.2 Internal data memory space
128-byte internal high-speed RAM is provided in the 78K0S/KU1+.
The internal high-speed RAM can also be used as a stack memory.
3.1.3 Special function register (SFR) area
Special function registers (SFRs) of on-chip peripheral hardware are allocated to the area of FF00H to FFFFH (see
Table 3-3
).
3.1.4 Data memory addressing
The 78K0S/KU1+ are provided with a wide range of addressing modes to make memory manipulation as efficient
as possible. The area (FE80H to FEFFH) which contains a data memory and the special function register (SFR) area
can be accessed using a unique addressing mode in accordance with each function. Figures 3-4 to 3-6 illustrate the
data memory addressing.
Figure 3-4. Data Memory Addressing (
µ
PD78F9200)
Special function registers (SFR)
256
×
8 bits
Internal high-speed RAM
128
×
8 bits
Flash memory
1,024
×
8 bits
Use prohibted
Direct addressing
Register indirect addressing
Based addressing
SFR addressing
Short direct addressing
F F F F H
F F 0 0 H
F E F F H
F F 2 0 H
F E 1 F H
F E 8 0 H
F E 7 F H
0 4 0 0 H
0 3 F F H
0 0 0 0 H