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µPD750008 USER'S MANUAL
Any line carrying a high pulsating current must be kept away as far as possible.
The grounding point of the capacitor of the oscillator must have the same
potential as that of VSS. It must not be grounded to a grounding pattern carry
ing a high current.
No signal must be taken directly from the resonator.
The subsystem clock oscillator has low amplification to minimize current con-
sumption. For this reason, more malfunctions can occur due to noise than the
main system clock oscillator. So pay special attention to wiring when using the
subsystem clock.
Figure 5-16 gives examples of oscillator connections which should be avoided.
Figure 5-16. Examples of Oscillator Connections Which Should Be Avoided (1/2)
(a) The wiring is too long. (b) The signal lines cross.
Remark When wiring the subsystem clock, read X1 and X2 as XT1 and XT2 respectively. In this case,
a resistor must be added to XT2 in series.
µPD750008
V
SS
X1 X2
µPD750008
V
SS
X1 X2
PORTn
(n = 0 to 8)