UPD17073 NEC, UPD17073 Datasheet - Page 18

• Manufacturer Part Number: UPD17073
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER WITH HARDWARE FOR DIGITAL TUNING SYSTEM
• Manufacturer: NEC

1.3 Processing of Unused Pins
18
Port pin
Pins other
than port
pins
Notes 1. The I/O ports are set in the input mode on power application, on clock stop, and on CE reset.
It is recommended that the unused pins be connected as follows:
2. When pulling up (connecting to V
Pin name
P0A0-P0A3
P0B0, P0B1
P0B2/SCK
P0B3/SI/SO1
P0C0, P0C1
P0D2/AMIFC
P0D3/FMIFC/AMIFC
P1A0, P1A1
P1A2/AD0
P1A3/AD1
P1B0-P1B3
P1C0/SO0
BEEP
CE
COM0-COM3
EO
INT
LCD0-LCD14
VCOH, VCOL
externally with high resistance, the pin almost goes into a high-impedance state, and consequently, the
current consumption (through current) of the port increases. Generally, the pull-up or pull-down
resistance is several 10 k , though it varies depending on the application circuit.
CMOS push-pull output
CMOS push-pull output
CMOS push-pull output
I/O
Input
Input
Output
Output
Input
CMOS push-pull output
Input
Table 1-1. Processing of Unused Pins
Note 1
I/O mode
DD
via resistor) or pulling down (connecting to GND via resistor) a pin
Open
Set by software to output low level and open
Connect each of these pins to V
Open
Open
Connect to V
Open
Connect to GND via resistor
Open
Connect each of these pins to GND via resistor
Recommended processing of unused pins
DD
via resistor
Note 2
Note 2
.
DD
.
or GND via resistor
PD17072,17073
Note 2
.
Note 2
.