L-1011 Avionics Bending: SFENA HSI and ARINC 429 - Part 12

Today's posting is all about integrating the FMS in to the HSI as the primary NAV instrument. Of course, on the L-1011 this would have been the INS or OMEGA. For the HSI demonstration today I am using the generic FMS in x-plane. The NAV mode of the HSI requires the following ARINC 429 labels to be integrated:

1. Magnetic Heading and/or True Heading (BNR)
2. NAV Course (BNR)
3. NAV Horizontal Deviation (BNR) 
4. NAV Vertical Deviation  (BNR)
5. Ground Speed (BCD)
6. Distance-To-Go in Nautical Miles (BCD) 

So, all in all quite a lot of different parameters. Each of the values is presented by x-plane and the SDK as a floating point number and requires the correct translation into either BNR or BCD format. If you are curious about the BNR encoding you can take a look at my previous post which shows how I convert the x-plane dataref to an ARINC 429 compatible BNR.

The video below demonstrates a takeoff from Seattle-Tacoma International Airport (KSEA) on a direct course to San Francisco International Airport (KSFO).