u-blox SARA-G3 Series System Integration Manual page 50

1.9.1.2 UART AT interface configuration
The UART interface is the only AT command interface on SARA-G3 series modules. UART is configured
as described in Table 9Table 9
Manual
[2]).
Interface AT Settings
UART interface AT interface: enabled
AT+IPR=0
AT+ICF=0
AT&K3
AT&S1
AT&D1
AT&C1
MUX protocol: disabled
Table 9: Default UART AT interface configuration
1.9.1.3 UART signal behavior (AT commands interface case)
At the module switch-on, before the UART interface initialization (as described in the power-on sequence
reported in Figure 13Figure 13), each pin is first tri-stated and then is set to its relative internal reset
6
state. At the end of the boot sequence, the UART interface is initialized, the module is by default in
active-mode, and the UART interface is enabled.
The configuration and the behavior of the UART signals after the boot sequence are described below. See
section 1.4 for definition and description of module operating modes referred to in this section.
RXD signal behavior
The module data output line (RXD) is set by default to the OFF state (high level) at UART
initialization. The module holds RXD in the OFF state until the module does not transmit some data.
5
Refer to the u-blox AT Commands Manual
mode.
6 See the pin description table in the SARA-G3 series Data Sheet [1].
UBX-13000995 - R06
SARA-G3 series - System Integration Manual
(for information about further settings, refer to the
Comments
AT command interface is enabled by default on the UART physical interface
Automatic baud rate detection enabled by default
Automatic frame format recognition enabled by default
HW flow control enabled
DSR line set ON in data mode5 and set OFF in command mode
Upon an ON-to-OFF transition of DTR, the DCE enters online command mode5 and
issues an OK result code
Circuit 109 changes in accordance with the Carrier detect status; ON if the Carrier is
detected, OFF otherwise
Multiplexing mode is disabled by default and it can be enabled by AT+CMUX
command.
The following virtual channels are defined for SARA-G350 modules:
Channel 0: control channel

Channel 1 – 5: AT commands / data connection

Channel 6: GNSS tunneling

The following virtual channels are defined for SARA-G300 and SARA-G310 modules:
Channel 0: control channel

Channel 1 – 2: AT commands / data connection

[2] for the definition of the interface data mode, command mode and online command
Objective Specification
u-blox AT Commands
5
System description
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