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3 FUNCTIONAL OVERVIEW
The Mark III CMU is designed to provide complete datalink capability, providing interfaces and support to today’s installed equipment. In addition, Honeywell as well as the industry recognizes that Datalink features will be expanded over time, and is in fact the principle behind the current ARINC 758 characteristic. A Characteristic that was developed to define current operation (referred to as Level O.1A), and allow expansion over time to support new requirements and needs. The Mark III CMU was specifically designed to support such future growth. Growth Functionality describes potential new capabilities for
The Mark III CMU supports an ARINC 739 MCDU, an ARINC 739 MIDU, and a CDU for displaying ACARS information. For the purpose of simplifying the text of this section, 'datalink display' will be used generically to mean MCDU, MIDU, or CDU.
3.1 Baseline Functionality
The baseline Mark III CMU provides functionality defined as level 0.1A in ARINC 758.
For Reference, the level of functionality as defined in the ARINC 758 Characteristic is shown below. This level of functionality is defined, as the CMU is recognized within the industry as evolving over time in order to meet future CNS/ATM requirements.
A758 level | Service Function |
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0 | ARINC 724B ACARS equivalent |
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| ARINC 618: ACARS |
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| ARINC 716: VHF |
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| ARINC 750: VHF Mode 0 |
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| ARINC 741: SATCOM |
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0.1 | + VDR Mode A using ARINC 429 I/F |
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| ARINC 750: Mode A |
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| ARINC 761: SATCOM |
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| ARINC 753: HF |
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0.2 | AOA VDLM2 |
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1 | + ATN Services |
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| ARINC 750: VDL Mode 2 |
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2 | + High Speed Services |
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| Not specified at this time |
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HONEYWELL Aerospace Electronic Systems | Page 18 |
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