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CHAPTER 2 PIN FUNCTION
2.2.7 AVREF
A/D converter reference voltage input pin.
When A/D converter is not used, connect this pin to VSS.
2.2.8 AVDD
Analog power supply pin of A/D converter. Always use the same voltage as that of the V
DD
pin even when A/D
converter is not used.
2.2.9 AVSS
This is a ground voltage pin of A/D converter. Always use the same voltage as that of the VSS pin even when A/
D converter is not used.
2.2.10 RESET
This is a low-level active system reset input pin.
2.2.11 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.
2.2.12 VDD
Positive power supply pin
2.2.13 VSS
Ground potential pin
2.2.14 VPP (
ยต
PD78P083 only)
High-voltage apply pin for PROM programming mode setting and program write/verify. Connect directly to VSS
in normal operating mode.