User's Manual

CL865-DUAL Hardware User Guide
1vv0301104 Rev.1 – 2014-03-07
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Reserved. Page 41 of 70
Mod. 0805 2011-07 Rev.2
9.2. Modem Serial Port 2
The secondary serial port on the CL865 is a CMOS 1.8V with only RX and TX signals.
The signals of the CL865 serial port are:
CL865
Pin No.
Signal
I/O
Function
Type
45
TXD_AUX
O
Auxiliary UART (TX data to DTE)
CMOS 1.8V
44
RXD_AUX
I
Auxiliary UART (RX data from DTE)
CMOS 1.8V
NOTE:
In order to avoid a back powering effect it is recommended to avoid having any HIGH logic
level signal applied to the digital pins of the CL865 when the module is powered off or during
an ON/OFF transition.