
36
Table 1-8 lists the pin functions for the HD404339 and HD404369 Series microcomputers.
Table 1-8
HD404339 and HD404369 Series Pin Functions
Type
Symbol
I/O
Function
Power supply
V
CC
—
Power supply: Connect to the system power supply.
GND
—
Ground: Connect to the system ground
AV
CC
—
Analog power supply: The A/D converter power
supply connection. Connect to a potential identical to
that of V
CC at a point as close as possible to the VCC
pin. Note that a bypass capacitor (about 0.1 F) should
be connected between the AV
CC pin and the AVSS pin if
a power supply separate from the V
CC power supply is
used for the A/D converter power supply. This
capacitor is not required if the AV
CC pin is connected
directly to the V
CC pin.
AV
SS
—
Analog ground: The A/D converter ground
connection. Connect to a potential identical to that of
GND at a point as close as possible to the GND pin.
V
disp
—
High voltage pin output power supply (HD404339
Series): Used as the output power supply by the high
voltage pins.
Clock
OSC
1
Input
System clock oscillator connection 1: Connect a
ceramic or crystal oscillator to this pin. Alternatively, an
external clock signal may be input to this pin. Use an
oscillator or clock with a frequency of between 400 kHz
and 4.5 MHz for the HD404339 and a frequency
between 400 kHz and 8.5 MHz for the HD404369. See
section 14, “Oscillator Circuits” for examples of the
circuits used when a ceramic or crystal oscillator or an
external clock is used.
OSC
2
Output System clock oscillator connection 2: Connect a
ceramic or crystal oscillator to this pin. Use an
oscillator with a frequency of between 400 kHz and
4.5 MHz for the HD404339 and a frequency between
400 kHz and 8.5 MHz for the HD404369. Leave this pin
open if an external clock is input to the OSC
1 pin.
X1
Input
Subsystem clock oscillator connection 1: Connect a
32.768 kHz crystal oscillator to this pin. Tie this pin to
ground if the subsystem clock is not used.
X2
Output Subsystem clock oscillator connection 2: Connect a
32.768 kHz crystal oscillator to this pin. Leave this pin
open if the subsystem clock is not used.