CHAPTER 3 CPU ARCHITECTURE
User’s Manual U16898EJ3V0UD
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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/KA1+ is provided with a wide range of addressing modes to make memory manipulation as efficient as
possible. The area (FE80H to FEFFH or FE00H to FEFFH) which contains a data memory and the special function
register area (SFR) can be accessed using a unique addressing mode in accordance with each function. Figures 3-3
and 3-4 illustrate the data memory addressing.
Figure 3-3. Data Memory Addressing (
µ
PD78F9221)
Special function registers (SFR)
256
×
8 bits
Internal high-speed RAM
128
×
8 bits
Flash memory
2,048
×
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 8 0 0 H
0 7 F F H
0 0 0 0 H