User Manual

Terminology
8-2 Confidential - For internal use 99-137719-D
8.1 Terminology
The control interface is the interface for controlling and configuring the BGAN XL Radio
Module. The control interface implements a proprietary protocol for exchanging
messages and data between a master and a slave. The BGAN XL Radio Module is the
slave. The unit responsible for controlling and configuring the BGAN XL Radio Module
is the master.
The messages transferred between the master and the RM are defined as Service Data
Units (SDUs). In Open Systems Interconnection (OSI) terminology, an SDU is a unit of
data that has been passed down from an OSI layer to a lower layer and that has not yet
been encapsulated into a Protocol Data Unit (PDU) by the lower layer. It is a set of data
that is sent by a user of the services of a given layer, and is transmitted semantically
unchanged to a peer service user. It differs from a PDU in that the PDU specifies the
data that will be sent to the peer protocol layer at the receiving end, as opposed to
being sent to a lower layer. A port number, similar to TCP/IP, is used by the framing
layer to identify the individual SDUs and their designated receiving service or
application.
8.2 Physical layer
The signals related to the physical layer of the Control Interface are listed in Table 5-15
on page 5-20. The UART configuration is listed below.
Figure 8-1: Control Interface between BGAN XL Radio Module and a board processor
Framing layer
Serial interface driver
Physical interface
CNAV
Services and applications
Radio Module
Framing layer
Serial interface driver
Physical interface
Control applications
Board processor
Serial link
RTS/CTS signaling
PDUs
SDUs
Link layer Link layer
USIM Management
Setting Value
Baud 115200
Parity none
Data bits 8
Stop bits 1
Flow control RTS/CTS
Table 8-1: Control interface UART configuration