ML865G1 HW Design Guide
1VV0301632 Rev. 4
Page
50
of
86
2020-09-23
NOTE:
According to V.24, some signal names are referred to the application
side, therefore on the ML865G1 side these signal are on the opposite
direction:
TXD on the application side will be connected to the receive line
(here named C103/TXD)
RXD on the application side will be connected to the transmit line
(here named C104/RXD)
For a minimum implementation, only the TXD, RXD lines can be
connected, the other lines can be left open provided a software flow
control is implemented.
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
ML865G1 when the module is powered off or during an ON/OFF
transition.
5.8.4.2.
Modem serial port 2 (USIF1)
The secondary serial port on the ML865G1 is a CMOS1.8V with only the RX and TX
signals.
The signals of the ML865G1 serial port are:
PAD
Signal
I/O Function
Type
NOTE
53
TX_AUX
O
Auxiliary UART (TX Data to
DTE)
CMOS
1.8V
Shared
with
SPI_MOSI
52
RX_AUX
I
Auxiliary UART (RX Data from
DTE)
CMOS
1.8V
Shared
with
SPI_MISO
