NEC NEC PD78081(A), User Manual

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CHAPTER 4 PORT FUNCTIONS
4.2.6 Port 10
This is an 2-bit input/output port with output latches. Input mode/output mode can be specified bit-wise by means
of port mode register 10 (PM10). When pins P100 to P101 are used as input port pins, an on-chip pull-up resistor
can be used as an 2-bit unit by means of pull-up resistor option register H (PUOH).
These pins are dual function pins and serve as timer inputs/outputs.
RESET input sets the input mode.
The port 10 block diagram is shown in Figure 4-9.
Figure 4-9. P100 to P101 Block Diagram
PUO : Pull-up resistor option register
PM : Port mode register
RD : Port 10 read signal
WR : Port 10 write signal
P-ch
WR
PM
WR
PORT
RD
WR
PUO
V
DD
Selector
PUO10
Output Latch
(P100 to P101)
PM100 to PM101
Internal bus
P100/TI5/TO5,
P101/TI6/TO6
Alternate
Functions