UPD780078 Datasheet, PDF (109/592 Pages) NEC – 8-Bit Single-Chip Microcontrollers

CHAPTER 6 PORT FUNCTIONS
Figure 6-13. Block Diagram of P34 to P36 (µPD780078Y Subseries)
WRPU
PU3
PU34 to PU36
VDD0
P-ch
Alternate
function
RD
WRPORT
WRPM
Output latch
(P34 to P36)
PM3
PM34 to PM36
Alternate
function
PU3: Pull-up resistor option register 3
PM3: Port mode register 3
RD: Read signal
WR××: Write signal
P34/SI3/TxD2,
P35/SO3/RxD2,
P36/SCK3/ASCK2
User’s Manual U14260EJ3V1UD
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