Telit Wireless Solutions HE910 - MODEM SERIAL PORT 2 (USIF1) Details

HE910 Hardware User Guide
1VV0300925 Rev. 32 Page 81 of 111 2019-11-25
MODEM SERIAL PORT 2 (USIF1)
The secondary serial port on the HE910 is a CMOS1.8V with only the RX and TX signals.
The signals of the HE910 serial port are:
The signal 1V8_SEL must be connected to the VDD_IO1 input pin in order to use this
port.
NOTE:
Due to the shared pins, when the Modem Serial port is used, it is not
possible to use the SPI functions.
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
HE910 when the module is powered off or during an ON/OFF
transition.
PAD
Signal
I/O
Function
Type
COMMENT
D15
TX_AUX
O
Auxiliary UART (TX
Data to DTE)
CMOS 1.8V
SHARED WITH
SPI_MTSR
E15
RX_AUX
I
Auxiliary UART (RX
Data from DTE)
CMOS 1.8V
SHARED WITH
SPI_MRST