CHAPTER 2. PIN FUNCTIONS

2.2.7X1, X2 (Crystal)

The built-in clock oscillation crystal/ceramic input.

It is also possible to supply the clock from the exterior.

(a) Crystal/Ceramic Oscillation

(b) External Clock

VDD

μ￿PD75402A

V DD

X1

X2

Crystal Resonator

or Ceramic Oscillator (Standard 4.194304 MHz)

External

Clock

μ￿PD74HC04

μ￿PD75402A

X1

X2

2.2.8RESET (Reset)

A low level active system reset input pin. It has Schmitt-triggered input and is built in with the noise eliminator by analog delay.

It has asynchronous input for RESET. It accepts a signal having a certain low-level width irrespective of the CPU’s operation clock if one is input and system reset is effected under priority over any other operation.

2.2.9VDD

A positive power supply pin.

2.2.10VSS

A GND potential pin.

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NEC PD75P402, PD75402A user manual 7 X1, X2 Crystal, Reset Reset