Cmsemicon CMS32L051 - 2.4 Handling of unused pins

V1.2.2
CMS32L051 User Manual |Chapter 2 Pin Function
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2.4 Handling of unused pins
The treatment of each unused pin is shown in Table 2-5.
Table 2-5 Handling of each unused pin
Pin name
Input/output
Recommended connection method when not in use
P00, P01
Input/output
Input: Individually connected via resistor EV
DD
or EV
SS
.
Output: Set to open.
P10~P17
P20~P27
P30, P31
P40
Input: Connect V
DD
individually via resistor or set it open.
Output: Set to open.
P41
Input: Individually connected via resistor EV
DD
or EV
SS
.
Output: Set to open.
P50, P51
P60, P61
Input: Individually connected via resistor EV
DD
or EV
SS
.
Output: Set the port's output latch to 0 and set it open, or set the port's output latch to 1
and individually
Connect E
VDD
or E
VSS
via resistors.
P62~P63
Input: Individually connected via resistor EV
DD
or EV
SS
.
Output: Set to open.
P70~P75
P120
P121~P124
Separate resistors connect V
DD
or V
SS
.
P130, P136
Input: Individually connected via resistor EV
DD
or EV
SS
.
Output: Set to open.
P137
Input: Connect V
DD
individually via resistor or set it open.
Output: Set to open.
P140, P146,
P147
Input: Individually connected via resistor EV
DD
or EV
SS
.
Output: Set to open.
RESETB
Input
Connect to V
DD
directly or via resistors.
Note: For products that do not have EV
DD
, EV
SS
pins, EV
DD
must be replaced with V
DD
and will EV
SS
is replaced with V
SS
.