Ublox MPCI-L2 series, System Integration Manual

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TOBY-L2 and MPCI-L2 series - System Integration Manual
UBX-13004618 - R07 Advance Information System description
Page 53 of 158
The “wake-up via data reception” feature cannot be disabled.
In command mode 7 , if autobauding is enabled and the DTE does not implement HW flow control, the DTE
must always send a character to the module before the “AT” prefix set at the beginning of each
command line: the first character is ignored if the module is in active-mode, or it represents the wake-up
character if the module is in idle-mode.
In command mode 7 , the DTE should always send a dummy “AT” before each command line: the first
character is not ignored if the module is in active-mode (i.e. the module replies “OK”), or it represents the
wake up character if the module is in low power idle-mode (i.e. the module does not reply).
No wake-up character or dummy “AT” is required from the DTE during a data call with external context
since the module UART interface continues to be enabled and does not need to be woken-up.
Furthermore in data mode
7
a dummy “AT” would affect the data communication.
Additional considerations
If the USB is connected and not suspended, the module is forced to stay in active-mode, therefore the AT+UPSV
settings are overruled but they have effect on the UART behavior (they configure UART power saving, so that
UART is enabled / disabled according to the AT+UPSV settings).
1.9.2.5 UART multiplexer protocol
TOBY-L2 series modules include multiplexer functionality as per 3GPP TS 27.010 [10], on the UART physical link.
This is a data link protocol which uses HDLC-like framing and operates between the module (DCE) and the
application processor (DTE) and allows a number of simultaneous sessions over the used physical link (UART): the
user can concurrently use AT interface on one MUX channel and data communication on another MUX channel.
The following virtual channels are defined (for more details, see
Mux implementation Application Note [11]):

Channel 0: control channel

Channel 1 – 5: AT commands / data connection

Channel 6: GNSS tunneling (not supported by “00”, “01”, “50” product versions)

Channel 7: SIM Access Profile (SAP, not supported by “00”, “01”, “50” product versions)
7 See the u-blox AT Commands Manual [3] for the definition of the interface data mode, command mode and online command mode.