
CHAPTER 4 PORT FUNCTIONS
User’s Manual U17854EJ9V0UD
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4.2.6 Port 5
Port 5 is an 6-bit I/O port with an output latch. Port 5 can be set to the input mode or output mode in 1-bit units
using port mode register 5 (PM5). When the P50 to P55 pins are used as an input port, use of an on-chip pull-up
resistor can be specified in 1-bit units by pull-up resistor option register 5 (PU5).
This port can also be used for external interrupt request input.
Reset signal generation sets port 5 to input mode.
Figures 4-18 and 4-19 show block diagrams of port 5.
Figure 4-18. Block Diagram of P50 and P51
P50/INTP1,
P51/INTP2
WRPU
RD
WRPORT
WRPM
PU50, PU51
PM50, PM51
EVDD
P-ch
PM5
PU5
P5
Output latch
(P50, P51)
Selector
Internal
bus
Alternate
function
P5:
Port register 5
PU5:
Pull-up resistor option register 5
PM5:
Port mode register 5
RD:
Read signal
WR
××: Write signal