[vlittle]

For those of you who have been following my original thread (EFIS flight data interchange protocols), you will see a lot of discussion ongoing with respect to next-generation (CAN based) protocols. I encourage that thread to continue, however, it has drifted off of the original objectives of the FIX (Flight Information eXchage) Protocol initiative.

Here are the stated objectives of the initial version of FIX:

Purpose

• To publish and promote the flight information data protocols supported by common Electronic Flight Information Systems and related devices.
• To work towards common protocols that support multi-vendor device interoperability and the development of third-party support devices.
• Targeted to the non-certified aircraft industry only.
• Not a standards organization, participation and compliance is strictly voluntary

Objective

• Collect and publish known protocols from all EFIS and related device vendors that wish to participate.
• Publish planned new protocols and seek comments and suggestions from all interested parties.
• Facilitate agreement on code points that will allow unique delineation and multiplexing of multiple protocols from multiple vendors on a single data link.
• Wherever possible, eliminate duplication of protocols by adopting or enhancing existing protocols.
• Wherever possible, ensure protocols are human readable (text based).

Process

• Collect and publish existing and newly developed protocols in a single location (this web site) to allow for easy access and comparison
• Publish newly planned protocols in a timely fashion to seek comments that lead to improvements and multi-vendor support
• Coordinate multi-vendor cooperation.
• Seek end-user requests for new features and functions.

Well, the initial objectives of the FIX initiative have been accomplished with release of the FIX 1.0 Interworking Protocols for Air Data and Engine Data

See the FIX website for more information, including other related protocols.

<continued>...

 

[vlittle]

...The FIX 1.0 protocol is supported by two of the heavy hitters in the EFIS market: Dynon and Garmin. As the intermediary in this process, I must complement both parties for cooperating and being flexible.

Both companies made changes to their proposed protocols in order to be virtually identical. Differing only in code points and minor implementation details, the Air Data and Engine Data protocols form the basis of a common interface specificaion that will allow third-party vendors to develop software and hardware products that can directly attach to serial ports from either vendor with a minimum of interworking problems.

I also received submissions from MGL that fell outside of the objectives, but provides very comprehensive information in proprietary fashion. This information is available on the FIX site as well.

Finally, the information that I have about AFS and GRT is that their protocols are based on the Chelton protocols which are unfortunately not publically available.

This initiative has proven to be quite time consuming for all of the parties involved, and I would like to declare victory and move on. I will offer my services in updating the FIX specification as required, and publishing any other protocols on the website that are applicable.

Should anyone find errors in the published specs, please let me know, but please try to keep this thread focused on FIX 1.0. The other (original thread) is more free-form discussion.

Thanks to everyone who has supported me on this, and especially the EFIS vendors who have participated in this otherwise thankless task.

Vern Little
Vx Aviation

 

[Dynon]

Just to note, the EMS data based on this standard is now shipping with 3.1 software in SkyView.

AHRS and SYSTEM data will be in the 3.2 release of SkyView's software.

Thanks to Vern for his work on this!