NEC PD78F9488 Manuale Utente
CHAPTER 4 PORT FUNCTIONS
User’s Manual U15331EJ4V1UD
89
4.2.7 Port 7
This is a 4-bit input-only port. Only the bits for which the port function is selected can be used, by using a mask
option in the
µ
PD789488 and 789489 or port function register 7 (PF7) in the
µ
PD78F9488 and 78F9489.
Figure 4-13 shows a block diagram of port 7.
Figure 4-13. Block Diagram of P70 to P73
P70 to P73
RD
Internal bus
RD:
Port 7 read signal