NEC switch User Manual
Page 33
CHAPTER 2 PIN FUNCTIONS
User’s Manual U12978EJ3V0UD
33
2.3 Pin I/O Circuits and Recommended Connection of Unused Pins
Table 2-1 lists the types of I/O circuits for each pin and explains how unused pins are handled.
Figure 2-1 shows the configuration of each type of I/O circuit.
Table 2-1. Type of Pin I/O Circuit Recommended Connection of Unused Pins
Pin Name
I/O Circuit Type
I/O
Recommended Connection of Unused Pins
P00 to P07
P10 to P17
5-R
P20/ SCK10
P21/SO10
P22/SI10
P23, P24
8-C
P25
P26/INTP0/TI01/TO01
8-F
P40/ KR00 to
P47/ KR07
8-C
Input:
Independently connect to V
DD0
, V
DD1
, V
SS0
, or V
SS1
via a
resistor.
Output: Leave open.
USBDM
Connect to the REGC pin.
USBDP
24-A
I/O
Independently connect to V
SS0
or V
SS1
via a resistor.
RESET
2
Input
—
NC
—
—
Leave open.
REGC
—
—
Connect to USBDM pin.
IC
Connect directly to V
SS0
.
V
PP
—
—
Independently connect a 10 k
Ω pull-down resistor, or connect directly
to V
SS0
.