LE940B6 HW User Guide
Rev. 2.02
Page 76 of 111
2020-01-10
NOTE:
To avoid a back-powering effect, it is recommended to avoid having any
HIGH logic level signal applied to the digital pins of the module when it is
powered OFF or during an ON/OFF transition.
NOTE:
The Auxiliary UART is used as the SW main debug console. It is required to
place test points on this interface even if not used.
8.2.3.
Modem Serial Port 3
Serial port 3 is a +1.8V UART with all 4 RS232 signals. It differs from the PC-RS232 in the
signal polarity (RS232 is reversed) and levels. Table 27 lists the signals of the LE940B6
Serial Port 3.
Table 27: Modem Serial Port 3 Signals
PAD
Signal
I/O
Function
Type Comment
AM9
UART3_TXD I
Serial data input (TXD) from DTE
1.8V
AM11 UART3_RXD O
Serial data output (RXD) to DTE
1.8V
AM13 UART3_RTS I
Input for Request to Send (RTS) from
DTE
1.8V
AM15 UART3_CTS O
Output for Clear to Send (CTS) to DTE 1.8V
NOTE:
To avoid a back-powering effect, it is recommended to avoid having any
HIGH logic level signal applied to the digital pins of the module when it is
powered OFF or during an ON/OFF transition.
Provided
to
Dekra
under
NDA
Distribution
is
Prohibited
except
for
Dekra
employees
with
a Need
to
know