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CHAPTER 2 PIN FUNCTION
Preliminary User’s Manual U16035EJ1V0UM
2.2.12 X1 and X2
Crystal resonator connect pins for main system clock oscillation.
For external clock supply, input clock signal to X1 and its inverted signal to X2.
2.2.13 XT1 and XT2
Crystal resonator connect pins for subsystem clock oscillation.
For external clock supply, input the clock signal to XT1 and its inverted signal to XT2.
2.2.14 V
DD0
and V
DD1
V
DD0
is a positive power supply port pin.
V
DD1
is a positive power supply pin other than port pin.
2.2.15 V
SS0
and V
SS1
V
SS0
is a ground potential port pin.
V
SS1
is a ground potential pin other than port pin.
2.2.16 V
PP
(flash memory versions only)
High-voltage apply pin for flash memory programming mode setting and program write/verify.
Connect directly to V
SS0
or
V
SS1
in the normal operating mode.
2.2.17 IC (mask ROM version only)
The IC (Internally Connected) pin is provided to set the test mode to check the
µ
PD780024AS, 780034AS Subseries
at delivery. Connect it directly to the V
SS0
or
V
SS1
pin with the shortest possible wire in the normal operating mode.
When a potential difference is produced between the IC pin and V
SS0
pin or V
SS1
pin, because the wiring between
those two pins is too long or an external noise is input to the IC pin, the user’s program may not operate normally.
• Connect IC pins to V
SS0
pins or V
SS1
pins directly.
As short as possible
IC
V
SS0
or
V
SS1