T E C H N I C A L D A T A
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Operating modes
Prommer mode
In the prommer mode, the device is connected directly to the FPS-8, FPS-21 or a similar prommer device. The
FBUS and MBUS signals are disconnected from the UART transceivers and RS-232 or USB ports are not used
during flashing.
The TW1m modem’s flashing mode is toggled by pulling the PROG_EN signal (System Connector 2’s pin 5) low.
The prommer mode is for Airbus R&D internal use only.
Data mode
In the data mode, the device may be controlled with AT commands from the terminal software and transfer data
packets as with DLR-8U Data Cable. AT tiny MCU handles conversion from MBUS to UART handshake signals for
flow control.
The USB or RS-232 interfaces are used for communication to MAB-1. RS-232 is used as default and MAB-1
enables USB connection when USB_VBUS voltage of 5V is detected. USB and RS-232 cannot be used
simultaneously.
The data mode is toggled by pulling the OPT_SEL2 I/O signal to low. After 6 seconds the data mode is ready to use.
Parametering mode
In the parametering mode, the device communicates with the Taqto TETRA programming tool using MBUS or
FBUS signals. Taqto selects the data bus by using the DTR handshake signal.
The USB or RS-232 interfaces are used for communication to MAB-1. RS-232 is used as default and MAB-1
enables USB connection when USB_VBUS voltage of 5V is detected. USB and RS-232 cannot be used
simultaneously.
The parametering mode is the default mode that is enabled when the OPT_SEL2 and PROG_EN signals are left
floating.
RF interface
The MAB-1 RF path is connected to the TH1n antenna springs. The TETRA- and GNSS antenna paths are
separated by a diplexer.
An assembly option without diplexer is possible when only the TETRA functionality is desired.
Audio
Microphone and speaker signals are routed directly from the TH1n side connector to System Connector 1.
Figure 5 RF interface
