Flight Director on D100

[Etienne(Guest)]

Would it be possible to devlope the ability to feed Flight Director information into the serial port and have it displayed on the EFIS? I'm designing a navigation system and will do all the calculations on a separate instrument, but would really like to have the output display on a D-100/D-180. Just a simple serial data stream with units of left/right/up/down. The sensitivity and offsets would be set by the supplying instrument, so the EFIS would purely need to read and display without any computations...

This system could be used, for example, to teach students how to fly a standard pattern...

Thanks
Etienne

 

[dynonsupport]

Hi Etienne,

Unfortunately, this currently isn't possible with our avionics. Our products do have RS-232 outputs that you can consume externally, but there is no facility to take data back in from an external device and display it.

 

[Etienne(Guest)]

That's a pity... :'(

Oh well, I guess it's there's nothing that few LED's or a small LCD can't display
Guess it'll keep me busy for a couple of days

Thanks for your reply
Etienne

 

[dynonsupport]

Currently there is no way to feed the EFIS external data for display.

 

[paul.mcallister]

Hi,

I apologize if I am going over old ground here. The ability to be able to display L/R and U/D information from external devices is very valuable.

Is this something the Dynon is probably not going to pursue in the near future, or never ?

Thanks, Paul

 

[dynonsupport]

Paul,
What kind of devices are you considering? The only standardized "up/down" and "left/right" information that we're aware of is a VOR/ILS system. Is this what you mean?

 

[Thomas_Schaad]

VOR/ILS system. Is this what you mean?

As I understand, Dynon has some GPS functions on hold as well, which probably will complement the now released DG in a nice and usefull manner.

What are the plans about VOR/ILS? Can that eventually be hooked up? It would make the system a kind of "complete", as those are basically the functions missing yet.

Kind regards

Thomas

 

[dynonsupport]

We have been showing the GPS "HSI" for a few months now and are working on it. It will be out in the next FW release. This gives a CDI needle that comes from the GPS, but no horizontal guidance.

The EFIS products don't have any way to hook up a NAV radio. No ARINC or resolver interface hardware is inside the unit, so we'll need to design an external box if we decide to do it. It's a future possibility for sure, but we don't have a timeframe for it.

 

[lucaberta]

Why would you need an external box, if one would choose to hook up a Garmin SL30 nav/com radio?

Every single bit of information can be found on the RS-232 wire, and the remote HSI head (your EFIS in this case) can instruct the SL30 on the OBS and frequency to use.

To me, that would be a (sorry for the overabused marketing term!) low hanging fruit... no need for hardware, and that would put you guys in line with some of your competitors on the HSI feature.

Ciao, Luca

 

[dynonsupport]

Putting out quality, stable, well thought out and crash-free software takes a lot more resources than hardware, so the biggest investment is there with today's systems.

If we do all the software work required for an HSI, we'll support a lot more than one radio. While many people have an SL-30, many more have Nav radios that don't have a serial port, and it doesn't make sense to make the software investment for 25% of our customers.

 

[lucaberta]

I rest my case.

While I agree on the cost of software development, it's because of the cost of hardware going down and software quality getting better that we can enjoy nice products like yours. And yet, software updates, while costly to debug and support, bring a lot of value to those existing customers who have already acquired your product.

So, to me supporting the SL30 would be just the very first step towards a full-blown nav radio support, which in my opinion might even look like building an hardware box that on one side would digest and spit out via RS-232 pretty much the same stream as the SL30, and on the other side would interface to the "old world" nav radios.

So we're back to square one; if you'd work on both the software and hardware side at the same time, maybe those nice SL30 features in the code might even become useful in the design of the interface box, and yet the many SL30 owners or prospect customers might take a different look at your product. I for one.

Thanks, Luca

 

[Thomas_Schaad]

I absolutely agree with lucaberta. I know quite a bunch of people, who didn't buy Dynon yet, as the NAV feature isn't available and not on the horizon either. I for my case was thinking deeply in removing the Dynon suit and replacing it with the Bluemountains EFIS Lite, I just didn't do as it won't fit in my panel and the Bluemountain Enginemonitor isn't as nice as yours, but NAV is essential.

On the high-end products, as Primus 1000 or Proline 4 etc, we basically buy an EFIS suit, including all: EFIS, EMS (EICAS), NAV etc. I think Dynon is on a good track and a good product could become a real runner having the NAV option available. NAV (GPS/VOR/ILS) is basically the only thing missing.  Even showing us a light on the horizon could be usefull  

Thanks for working out all those nice goods for us, in the past, the present and....... the future, kind regards

Thomas

 

[paul.mcallister]

Hi,

I would seem that my question sparked a lot of activity. I guess that is a good indicator as to the interest on having the ability to have CDI information displayed in front of them. For me I am mostly interested to have CDI information displayed when doing approaches. This would mean data from either approach certified GPS units or analogue ILS/LOC units

Ignoring the commercial realities for the moment, the end state would probably mean support for the serial data streams from Apollo SL30's, Apollo GX50~60 series approach GPS units, the Garmin 430 / 530 products and finally, the good old fashion analogue ILS/LOC units. Given that the Dynon unit only has the possibility for serial inputs, this is a tall order. One approach might be to support all of the serial devices making it a menu configuration and never supporting the analogue ILS/LOC units.... not a trivial exercise when it comes to software development.

From a design perspective I would probably insert a microprocessor "black box" in between the Dynon and the target device. Devices such as the PIC support serial input(s), outputs and A/D converters for the analogue ILS/LOC inputs. The only concern I would have is the high speed 115k baud serial speeds used by Dynon would force me to write the serial output routines in assembly language, I guess the rest could be written in a high level language such as C or PicBasic.

So, in short, this would be a significant development effort with quite a pay back period. Perhaps the most economical approach would be to incorporate the flight director display functions in the Dynon, publish the protocol, and lets the public domain "have at it". I would be up for having a go and publishing the results, but I would expect that this would take 6 months of my spare time.

Sorry about such a long winded reply, but I would encourage Dynon to give this approach some thought. This would be the least amount of development effort required by Dynon and puts the possibility of a solution our into the public domain to solve.

Regards, Paul

 

[dynonsupport]

Paul,

Just a few notes:

Only the SL30 will publish/recieve ILS/VOR information over serial. The 430 / 530 will only do the VOR/ILS digitally over ARINC 429, or via the old analog interface. I believe the GX series is the same way. As far as I know, the SL30 is the only radio around that can be used via a serial link.

The trickiest part of the analog interface is the OBS setting. To do this, you have to emulate a transformer with sine and cosine coils, not just a simple slow A/D on that line. Without the OBS ring, you would need an external HSI or VOR display or the radio wouldn't work, which kind of defeats a big part of the advantage of having the displays on the EFIS.

Interfacing with analog NAV units can be done, but it's not a simple thing to do at all.

 

[paul.mcallister]

Dynon Support,

I love these forums, I have just learnt a few new things. I must admit to having giving the OBS aspect to it no thought at all. Part of this is because I have my head around only doing GPS and ILS approaches. I just never use my VOR any more, I do it all on my GX60.

So, I guess for me I wouldn’t care about the lack of an OBS feature, however I doubt that this would be satisfactory for many. However, I believe that my original suggestion has merit, you could put the flight director code in your product and publish the protocol.

Conversely, if the SL30 is the only product that does this in a serial format you could build this into your product and if anyone wanted to experiment with “black boxes” then they would simply make it emulate the SL30 protocol on the output side.

Interesting problem, thanks for engaging me the dialogue it has been most enlightening.

Paul

 

[Etienne]

I believe that my original suggestion has merit, you could put the flight director code in your product and publish the protocol.

Conversely, if the SL30 is the only product that does this in a serial format you could build this into your product and if anyone wanted to experiment with “black boxes” then they would simply make it emulate the SL30 protocol on the output side.

I'm glad I'm not alone here, and that I stuck my head around the door again. I am working on an alternative to this problem which will require a new screen, powered by a laptop, pretty much replicating everything the efis shows already, but with an added boxes-in-the-sky view. Although this is slightly different to the standard flight director (as it shows what's coming up as well as the current situation), the simple flight director would suffice.

I'm not familiar with the software structure of the efis (obviously ) but surely it wouldn't be too hard to add a set of magenta crosshairs driven by the serial port (using any protocol, if not the Garmin one)? The added risk of a software crash should be negligable, in my humble opinion. The added out-of-the-box may only impact 25% of your customer base, but it's another feather in the cap, and will definately make people consider Dynon more seriously. I may be wrong here, but from what I've seen, a huge amount of efis's go into new panels, where the cross-compatibility of instruments is a big deciding factor. People would buy the Garmin because it speaks to the D-10(0). Conversely, people would buy the D-10(0) because it speaks to the Garmin.

The new DI is fantastic, by the way! Thankyou

 

[Etienne]

You guys are the best! I'm really glad I spent the dosh and went with Dynon. Everything I could have wanted its gradually being added to the D-100! The input from the SL30 looks like it will do the job, if I can replicate the protocol successfully.

You guys should consider approaching Airbus, they may be interested