Internal Data Memory Space; Special Function Register (Sfr) Area - NEC 78K0/KD1 Series User Manual

3.1.2 Internal data memory space

78K0/KD1 Series products incorporate the following internal high-speed RAMs.
Part Number
µ PD780121
µ PD780122
µ PD780123
µ PD780124
µ PD78F0124
The 32-byte area FEE0H to FEFFH is assigned to four general-purpose register banks consisting of eight 8-bit
registers per one bank.
This area cannot be used as a program area in which instructions are written and executed.
The internal high-speed RAM can also be used as a stack memory.

3.1.3 Special function register (SFR) area

On-chip peripheral hardware special function registers (SFRs) are allocated in the area FF00H to FFFFH (refer to
Table 3-5 Special Function Register List in 3.2.3 Special Function Registers (SFRs)).
Caution Do not access addresses to which SFRs are not assigned.
CHAPTER 3 CPU ARCHITECTURE
Table 3-4. Internal High-Speed RAM Capacity
512 × 8 bits (FD00H to FEFFH)
1024 × 8 bits (FB00H to FEFFH)
Preliminary User's Manual U16315EJ1V0UD
Internal High-Speed RAM
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