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

(2) CALLT instruction table area
The 64-byte area 0040H to 007FH can store the subroutine entry address of a 1-byte call instruction (CALLT).
(3) CALLF instruction entry area
The area 0800H to 0FFFH can perform a direct subroutine call with a 2-byte call instruction (CALLF).
3.1.2

Internal data memory space

78K0/KF1 products incorporate the following RAMs.
(1) Internal high-speed RAM
The internal high-speed RAM is allocated to the area FB00H to FEFFH in a 1024 × 8 bits configuration.
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.
(2) Internal expansion RAM
Part Number
µ
PD780143
µ
PD780144
µ
PD780146
µ
PD780148
µ
PD78F0148
The internal expansion RAM can also be used as a normal data area similar to the internal high-speed RAM, as
well as a program area in which instructions can be written and executed.
3.1.3

Special function register (SFR) area

On-chip peripheral hardware special function registers (SFRs) are allocated in the area FF00H to FFFFH (see
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.
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CHAPTER 3 CPU ARCHITECTURE
Table 3-4. Internal Expansion RAM Capacity
1024 × 8 bits (F400H to F7FFH)
User's Manual U15947EJ2V0UD
Internal Expansion RAM
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