Click image to view original
The ARINC 717 bus defines the communication between DFDAU(Digital Flight Data Acquisition Unit) and the DFDR(Digital Flight Data Recorder). The Data over the bus is a collection of all vari
ous data to be recorded.
The Data is organized in 4 subframes each 1 second long, which comprise one frame of 4 seconds. Each subframe contains 64 (or 128 or 256) words of 12-bit each. Each subframe starts with a unique synch word and these 4 words are known as Barker Code and are used to synchronize on new frame. The electrical signals of this bus are +/-5V differential pair Harvard Bi-Phase coded. The various data words are continuously transmitted in their chronological order and can be recognized by their predefined relative location in frame.
1e Fully Integrated
Excalibur’s Dragon is an advanced, ruggedized PC104 and PC104+ system in an enclosed, modular casing. The system is appropriate for use in data acquisition and recording for any combination of ARINC-429, MIL-STD-1553, Serial, Discrete or similar types of communication. The modular, stackthrough design of the PC104/PC104+ platform allows you to build a tailormade configuration based on Excalibur’s extensive range of boards while permitting the integration of other commercially available PC104/PC104+ cards. This modularity also enables the Dragon to be modified or upgraded at any time as technology and requirements change. The Dragon includes a processor card, a power supply and a selecion of Excalibur’s ARINC-429 and MIL-STD-1553 boards. Each unit is heat sink protected, enabling an internal operational temperature range fro -40°C to +85°C. The unit comes with military style waterproof connectors and seals between rings to impede water incursion as well as EMI/RFI protection to the inner electronics. Its compact footprint allows for versatility when space is at a premium.