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CHAPTER 3 PIN FUNCTION (
μ
PD780058 Subseries)
3.2.10 P130 and P131 (Port 13)
This is a 2-bit input/output port. Besides serving as an input/output port, it is used for a D/A converter analog output.
The following operating modes can be specified bit-wise.
(1) Port mode
This port functions as a 2-bit input/output port. It can be specified bit-wise as an input or output port with port
mode register 13 (PM13). When it is used as an input port, on-chip pull-up resistors can be used by defining
the pull-up resistor option register H (PUOH).
(2) Control mode
This port allows D/A converter analog outputs (ANO0 and ANO1).
Caution When only either one of the D/A converter channels is used with AV
REF1
< V
DD0
, the other pins
that are not used as analog outputs must be set as follows:
Set PM13x bit of the port mode register 13 (PM13) to 1 (input mode) and connect the pin
to V
SS0
.
Set PM13x bit of the port mode register 13 (PM13) to 0 (output mode) and the output latch
to 0, to output low level from the pin.
3.2.11 AV
REF0
An A/D converter reference voltage input pin. This pin also serves as an analog power supply pin. Supply power
to this pin when the A/D converter is used.
When the A/D converter is not used, use the same voltage that of the V
SS0
pin.
3.2.12 AV
REF1
A D/A converter reference voltage input pin.
When the D/A converter is not used, use the same voltage that of the V
DD0
pin.
3.2.13 AV
SS
This is a ground voltage pin of A/D converter and D/A converter. Always use the same voltage as that of the V
SS0
pin even when the A/D converter or D/A converter is not used.
3.2.14 RESET
This is a low-level active system reset input pin.
3.2.15 X1 and X2
Crystal resonator connect pins for main system clock oscillation. For external clock supply, input it to X1 and its
inverted signal to X2.
3.2.16 XT1 and XT2
Crystal resonator connect pins for subsystem clock oscillation.
For external clock supply, input it to XT1 and its inverted signal to XT2.
3.2.17 V
DD0
, V
DD1
V
DD0
is the positive power supply pin for ports.
V
DD1
is the positive power supply pin for blocks other than port and analog blocks.