NEC PD78F9488 Manuale Utente

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CHAPTER  3   CPU  ARCHITECTURE 
 
User’s Manual  U15331EJ4V1UD
 53 
3.1.2  Internal data memory space 
(1)  Internal high-speed RAM and internal low-speed RAM 
The 
µ
PD789489 Subseries products incorporate the internal high-speed RAM and internal low-speed RAM of 
the following capacity for each product. 
The internal high-speed RAM can also be used as a stack. 
The internal low-speed RAM cannot be used as a stack. 
 
Table 3-3.  Internal High-Speed RAM, Internal Low-Speed RAM Capacity 
Part Number 
Internal High-Speed RAM 
Internal Low-Speed RAM 
µ
PD789488 
µ
PD78F9488 
− 
µ
PD789489 
1024 
× 8 bits 
µ
PD78F9489  
512 
× 8 bits 
 
(2)  LCD display RAM 
LCD display RAM is incorporated in the area between FA00H and FA1BH. 
The LCD display RAM can also be used as ordinary RAM. 
 
3.1.3  Special function register (SFR) area 
Special function registers (SFRs) of on-chip peripheral hardware are allocated in the area between FF00H and 
FFFFH (see Table 3-4).