User's Manual

SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
eNfusion® HSD-440 Mark 2 Terminal
23-15-30 F-2
3 JUN 10
The CMU transmits its position in
the cockpit to the HSD-440 Mark 2 Terminal using bits
9 and 10, as shown in Table F-2.
Table F-2 Bits 9 and 10 Positions
SDI 1 (bit 9) SDI 2 (bit 10) Position
0 0 Single
0 1 Left
1 0 Right
1 1 Not used
Attachment 6 from ARINC Characteristic 758 de
scribes the word format of this label.
C. Understanding Status Word 2; Label 276
Each CMU transmits status word 2 to the HSD-440 Mark 2 Terminal. The HSD-440 Mark
2
Terminal determines which CMU is sending the message based upon bits 9/10 (the
SDI) as detailed in Table F-2.
The HSD-440 Mark 2 Terminal uses the SAT Link parameter (bit 19) to determine if the
CMU is
receiving the appropriate link status from the HSD-440 terminal.
Attachment 6 from ARINC Characteristic 758 de
scribes the word format of this label.
D. Understanding Protocol File Transfer to SDU1 via Williamsburg
Data is transferred to the HS
D-440 Mark 2 Terminal using Williamsburg protocol.
Williamsburg messages use the SAL of the equipment they are talking to as the label. In
this case, the label is 307 as the sub-system identifier label sent from the HSD-440 to
the CMU is 307. For more information, refer to "Understanding Word Format" on page
F-7.
2. Understanding Messages Received from the HSD-440 Mark 2 Terminal
This section provides details about the words sent from the HSD-440 Mark 2 Terminal from the
CMUs:
• Understanding System Ide
ntification Label 172
• Understanding Status Word 1; Label 270
• Understanding Join/Leave Word; Label 271
• Understanding Protocol File
Transfer to CMU via Williamsburg
A. Understanding System Identification Label 172
The HSD-440 Mark 2 Terminal transmits subsytem id
entifier label 172 which contains
the subsystem SAL in bits 9 to 16. The SAL is set to 307 (octal). Also:
• Bit 17 is set to indicate Inmarsat Aero
• Bits 18-31 are used for other Satcom ser
vices (or are spare) and are set to 0