User's Manual

SIM7075G User Manual V1.00
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One channel full-function serial port UART1, it can be used for AT command communication between the
module and the peripheral MCU.
One channel 2-wire serial port UART3, the default function after booting is GPIO. It can be configured as a
UART function, but it cannot be used for AT command communication. It is only used as UART in DAM
(Downloadable Application Module) application when secondary development. It can also be configured as
a GNSS NMEA data output port.
One channel serial port DEBUG_UART, the boot log will be output from hear during the system boot-up.
The default function after booting is GPIO. It can be configured as a UART function, but it cannot be used
for AT command communication. It is only used as UART in DAM (Downloadable Application Module)
application when secondary development.
When the UART port is used as the AT communication port, it supports high speed mode, the baud rate is
up to 4Mbps.
The communication baud rates include:
0,300,600,1200,2400,4800,9600,19200,38400,57600,115200,230400,921600,2000000,3000000,3200000
and 3686400 bps.
The rate 0bps marks auto baud rate. And it supports auto baud rate, but the rate only supported on 9600,
19200, 38400, 57600, 115200. If users need to change to other baud rate, it needs to switch via manual
operation.
3.3.1 UART Design Guide
The following figures show the reference design.
Figure 11: UART full modem