Filter
Top Products
2-10
APPLICATION
2.1 I/O pins
4513/4514 Group User’s Manual
Table 2.1.6 connections of unused pins
Pin
XOUT
VDCE
D0–D5
D6/CNTR0
D7/CNTR1
P20/SCK
P21/SOUT
P22/SIN
P30/INT0
P31/INT1
P32, P33
P40/AIN4–P43/AIN7
P50–P53 (Note 1)
AIN0/CMP0-
AIN1/CMP0+
AIN2/CMP1-
AIN3/CMP1+
P00–P03
P10–P13
Connection
Open (when using an external clock).
Connect to VSS.
Connect to VSS, or set the output latch to “0” and open.
Connect to VSS.
Connect to VSS, or set the output latch to “0” and open.
Connect to VSS, or set the output latch to “0” and open.
When the input mode is selected by software, pull-up to VDD through a resistor or
pull-down to VSS. When selecting the output mode, open.
Connect to VSS.
Open or connect to VSS (Note 2).
Open or connect to VSS (Note 2).
Notes 1: After system is released from reset, port P5 is in an input mode (direction register FR0 = 00002)
2: When the P00–P03 and P10–P13 are connected to VSS, turn off their pull-up transistors (register
PU0i=“0”) and also invalidate the key-on wakeup functions (register K0i=“0”) by software. When
these pins are connected to VSS while the key-on wakeup functions are left valid, the system fails
to return from RAM back-up state. When these pins are open, turn on their pull-up transistors
(register PU0i=“1”) by software, or set the output latch to “0.”
Be sure to select the key-on wakeup functions and the pull-up functions with every two pins. If
only one of the two pins for the key-on wakeup function is used, turn on their pull-up transistors
by software and also disconnect the other pin. (i = 0, 1, 2, or 3.)
(Note in order to set the output latch to “0” and make pins open)
• After system is released from reset, a port is in a high-impedance state until the output latch of the port
is set to “0” by software. Accordingly, the voltage level of pins is undefined and the excess of the supply
current may occur.
• To set the output latch periodically is recommended because the value of output latch may change by
noise or a program run away (caused by noise).
(Note in order to connect unused pins to VSS or VDD)
• To avoid noise, connect the unused pins to VSS or VDD at the shortest distance using a thick wire.