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SDS EM-6 EFI ECU

Not much, most time lately has been spent on getting the CPI2 into production and that will probably still be the case until the end of the year. We have also received multiple orders in the last week which will take us well into December. Production takes some time away from R&D of course but we need that money to come in for EM-6 development.

We have been re-evaluating the processor choices a bit more last week as one military client has interest is using the EM-6 on a new engine type with somewhat different requirements than our usual 4, 6 and 8 cylinder applications.

CPU choice needs to be decided before any serious hardware or software design starts. We want to be sure the new hardware can deal with any popular engine design used or currently under development for aviation.

We did learn some useful things and lessons on the CPI2 development which will be spun into the EM-6 design and software.

New ECU boards takes many months of design and testing before they can be released for sale, ditto for the new code that goes with them.
 
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Is the ?upgrade? to EM-6 offer from Post 1 going to be available to 2019 purchasers as well? I?m still several months from needing to order so I?m trying to find out if I should order now or wait until EM-6 is released, even if that means waiting till next December...
 
Yes, the EM-6 upgrade will be available to anyone who purchased a full aviation EFI system in 2018 or 2019. The main point of this is so that people who are ready to complete their aircraft don't have to wait to go flying and us showing our appreciation for people choosing SDS.
 
Will the EM-6 work on odd number cylinder engines like radials?
Will it have a complex lookup table compatible with IAC aerobatic load profiles?
The upgrade would be nice. Besides, the carb and mags on my Yak are not well supported.
I?m pretty sure you could sell two ...
 
Will the EM-6 work on odd number cylinder engines like radials?
Will it have a complex lookup table compatible with IAC aerobatic load profiles?
The upgrade would be nice. Besides, the carb and mags on my Yak are not well supported.
I?m pretty sure you could sell two ...

We've had at least 4 people contacting us over the years to do EFI on radials but none have followed through. Pretty easy to do fuel only, a lot harder to do spark on odd numbers of cylinders. Would need a crank sensor signal at crank or cam speed. A lot of these engines are geared and therein lies the problem usually.

Could be done but how big is the market these days? We can only put effort into markets with a decent chance of return.

Our standard 2D programming gives good driveability on cars which can have all kinds of MAP and rpm combinations. No reason why it won't work here.

The EM-6 will be aimed initially at the usual 4, 6 and 8 cylinder engines which make up 95% of the aviation market. If we have time and someone can figure out where to get the rpm signal from, we would be interesting in pursuing this.
 
Ross,

Have you thoughts about continuing to sell your inventory of EM5F once the EM6's are released? (for those who may not want or need the advanced functionality of the EM6?

Charlie
 
The remaining new EM-5 inventory would be sold to whoever wants them. We'll probably also have a number of relatively new, returned EM-5 boards when we start subbing them out for EM-6s for our recent aviation system customers. The plan was to offer these at reduced prices to our automotive customers if desired. They could also go to aviation customers too I suppose.

The decision hasn't been made to continue EM-5 production yet. We occasionally run an older EM-5 board for a military customer because that is the version they vetted quite a number of years ago and don't want to go through that process again.

The good news is that the new programmers under development now are planned to be able to be used with EM-5 ECUs, with a reflash.
 
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The remaining new EM-5 inventory would be sold to whoever wants them. We'll probably also have a number of relatively new, returned EM-5 boards when we start subbing them out for EM-6s for our recent aviation system customers. The plan was to offer these at reduced prices to our automotive customers if desired. They could also go to aviation customers too I suppose.

The decision hasn't been made to continue EM-5 production yet. We occasionally run an older EM-5 board for a military customer because that is the version they vetted quite a number of years ago and don't want to go through that process again.

The good news is that the new programmers under development now are planned to be able to be used with EM-5 ECUs, with a reflash.


Ross,

Thank you for a quick reply.

For those of us who have older EM4 and EM5 CPU installed, will we be able to plug our existing plugs directly in to the EM6?

Charlie
 
Ross,

Thank you for a quick reply.

For those of us who have older EM4 and EM5 CPU installed, will we be able to plug our existing plugs directly in to the EM6?

Charlie

The pin outs on the ECUs have remained the same since the EM-3 in 1999 and we intend to keep those the same in the EM-6 for retro-compatibility reasons.

Since late 2017, we've added 2 additional wires to the DB25 connector on all aviation harnesses so that these pins are available when making a change to the EM-6 to enable new features.

Plans at this time are to move the serial output jack to the end of the case and add an additional connector in its place to provide more pins for other new features. This would be in the form of a small sub-harness which can be easily added to existing systems.

We try to do our best not to orphan older systems but it's impossible to forecast 20 years into the future what features will be desired or developed.
 
We try to do our best not to orphan older systems

And that deserves yet another pat on the back------pretty unusual in today's world of planned obsolescence.

Thank you.

Are you going to Reno this year, we need to talk about outfitting the new plane's engine.
 
Mike, yes, I'll be at Reno supporting the many racers running SDS this year. Will be good to see you again.
 
Update

It's been a while since we updated this thread.

We are currently working on the new panel mount programmers which will be compatible with both EM-5 and EM-6 ECUs. Most of the design for one is done now and some parts have already started the production process while others will go to prototyping next week. Code is already written for these to interface.

Given the great positive feedback we've received from potential and past customers, I think you'll like what we designed.

I anticipate release of the first design in October if all goes well. The second design will hopefully be in production in Dec.

I can't say much more than that until we are closer to release.
 
It's been a while since we updated this thread.

We are currently working on the new panel mount programmers which will be compatible with both EM-5 and EM-6 ECUs. Most of the design for one is done now and some parts have already started the production process while others will go to prototyping next week. Code is already written for these to interface.

Why two different programmers?

Also, would you advise just waiting a month or two on ordering a full system at this point? I'm definitely not in an urgent need for it and can afford the wait; I'll find other parts to work on.
 
We wanted to give our customers more choices which will fit their panel space. Research showed this to be a big deal. There are a lot a new builds with glass and still a lot of retrofits in some older aircraft with steam.

The programmers will be EM-5 compatible and released well before the EM-6 ECU becomes available. We want customers to have it's advantages sooner rather than later.

If you can wait, you'll have both choices.
 
Our usual procedure is to wait until we have all the hardware in hand and working before we release photos.

The face was approved for production last week so that's in process now. That usually takes around 4 weeks.

Prototype enclosure CNC machining will start next week.

Should have proto PCBs by this Friday.
 
New Programmers

Production keypads for Design 1 will be shipped Oct. 10th. Proto PCBs are being tested now. Proto enclosure machining was delayed 2 weeks while the machine shop replaced one mill with a new 4 axis machine. These should be done mid next week to test fit.

We hope to release final sizes and photos in mid Oct. once testing is completed. If all goes well, we should be able to release some in early Nov.

Design 2 work will begin in mid October.
 
Design1 Programmer

Ok, many folks have been waiting to see what the new EM-6 programmers will look like for some time. As always, things take longer to do than you plan.

We looked at many different sizes and types of displays over the last year and were heading towards a large touch screen early on. Bought some screens and CPUs to dabble with but in listening to feedback from customers, they kept telling us to keep it small- they didn't have a lot of panel space to put something big with their large glass displays. Listening to our customers has served us well in the last few years as we have developed the features most wanted- cylinder trim, LOP timing advance, easier to mount injectors etc.

I did a big evaluation here on VAF, downloading over 40 photos of modern RV panels and came to the conclusion we really did need something different than what we were working on. I saw the only place many people had vacant panel space was above the center stack, in the dead space near the top of the panel arch.

We also evaluated the function vs wow factor of touch screens for these devices. Once programming is completed, most people don't use the programmer so much any more, outside of cylinder trim, the LOP switch, gauge modes and maybe looking at a fault code once in a while. We therefore discarded the big, square TFT display and went for the smallest practical display and keypad we could make to fit the maximum number of glass panels. A couple months lost but I think this design will fit modern panels much better and make more people happy.

Here is what we came up with for Design1.



This will be 6.25 X 1.47 inches to fit the normal stack width. Total box depth is less than 2 inches, allow around 4 inches with data cable exits. It will have a blue background LCD (not green as in the photo above) with white alphanumerics to match the recent look of the CPI-2 display which people really liked. The shape and colors fit better with Garmin, Dynon/AFS and MGL glass as we saw in Mike Kellems' CPI-2 post a couple weeks ago.

We also listened to customers who said we should eliminate as many external switches as possible. So we've made the programmer select switch to access either ECU, integral with the keypad as well as the LOP switch with dedicated keys and status LEDs similar to the CPI-2. We've also fitted the check engine light (now called Fault) in the programmer face to eliminate that external light and wiring.

Touch screens were not an option for this size and shape and many people said they prefer the tactile feeling of membrane switches anyway.

We'll follow in early 2020 with a second programmer choice-Design2, which will be the same size and shape of the present EM-5 aviation programmer (fits in a standard 3 1/8 round hole). This will have the same colors, graphics and functions as Design1 above. Some people do have room for this shape or may want to upgrade from an earlier type programmer to this one at some point and don't want to cut new holes in their panels.

These new programmers will be introduced into the EM-5 lineups as soon as they are in production and older EM-5s can use them if re-flashed with new software.

We did leak some basic dimensions to customers working on panels and response has been really positive with this new shape so I think we may have made a good call.

Thanks to everyone who gave us comments and feedback during the evaluation and design stage. That helped correct our path and come up with something that suits more panels.
 
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Ross,

Looks great. I for one am somewhat glad touchscreen is not incorporated. Great to see innovation with a high degree of customer input involved.

I would much rather have buttons that are easy to see and find that a touch screen. Best of all you don't have to hunt to find just that right spot on a touch screen to activate a function. I am also glad it is LCD and not LED. I have learn that even the brightest LED get washed out in bright sunlight, but LCD are not affected.

I am sure they will sell well.

Charlie
 
Design1 Programmer and EM-6

Hi Ross,

The Design1 Programmer looks great and I am happy you choose this form factor for all the reasons you gave in your post above.

I hope the programmer LED ?s A/B are extinguished when NOT in the programmer mode and that you make the Fault LED red. Just a small point, I noticed that the bezel on the right is bigger than on the left, I think it would be more beautiful when they are equal. Where will the Mixture knob be?

I know I am way too late to give input for the new EM-6, but here goes anyway.
I would love to see the following features:
Ability to program 3 different ignition/fuel maps, to be chosen via the LOP button.
MAX PWR, the ignition/fuel maps are programmed to give maximum power on the ROP side, staying just outside the red box, but without wasting any more fuel then necessary.
ECON, the ignition/fuel maps are programmed to give ?maximum? power on the LOP side, staying just outside the red box. This power is arbitrarily chosen, but I would choose just below LOP, for instance 25 degrees LOP, resulting in a relatively low speed loss.
ECON +, the ignition/fuel maps are programmed to give the maximum fuel efficiency. This power is also arbitrarily chosen, for instance 75 degrees LOP, resulting in minimum fuel flow, but accepting a much bigger speed loss.
Both Econ settings would be programmed with ROP values above 75% power and/or the ECU would automatically switch to the MAX PWR map when it sees power settings above 75%. This feature would make it literally foolproof, so you always have max power ROP available for take off and go around. Of course the LOP LED on the programmer should follow this auto switching.
Ability to have ?automatic? cylinder fuel trim for all power settings. During test flights we find what individual fuel trim is needed to have the EGT?s peak at the same time for several MAP and RPM combinations. This information is then ?overlaid? on the ignition/fuel map so we get automatic individual fuel trim at these MAP/RPM settings with an interpolation between these points.

The new programmer will sit in a high visibility spot, so when not in program mode it can be used as an annunciator. It can show for instance the chosen power mode MAX PWR, ECON or ECON + and % power and AFR. When there is an anomaly this will be replaced by for instance ECU1 or ECU2, IGN1 or IGN2, FUEL PRESSURE, BUS1 xx V, or BUS2 xx V. The fault codes should be on a separate page. Ideally the white alphanumerics should change color to red or amber or alternatively the whole screen could change color from blue to amber or red. It is important to have a visible change otherwise it will be very easy to miss.
Also I find it important to see not only the LOP LED illuminated but also the power mode annunciation when LOP is chosen, again because a little LED will be overlooked very easily.
As far as the % power is concerned, I know there is no operational need for it and that often it is not very accurate. But with all the data available to the ECU you should be able to calculate a reasonable number and it is nice to have. As far as AFR is concerned, also no operational need, but it is a very nice indicator of your fuel efficiency. I plan on mostly using unleaded fuel so the Oxygen sensor should survive. Give the users some freedom to decide what they want to see on this page and everybody will be happy.

Gordon
 
Hi Ross,

The Design1 Programmer looks great and I am happy you choose this form factor for all the reasons you gave in your post above.

I hope the programmer LED ‘s A/B are extinguished when NOT in the programmer mode and that you make the Fault LED red. Just a small point, I noticed that the bezel on the right is bigger than on the left, I think it would be more beautiful when they are equal. Where will the Mixture knob be?

I know I am way too late to give input for the new EM-6, but here goes anyway.
I would love to see the following features:
Ability to program 3 different ignition/fuel maps, to be chosen via the LOP button.
MAX PWR, the ignition/fuel maps are programmed to give maximum power on the ROP side, staying just outside the red box, but without wasting any more fuel then necessary.
ECON, the ignition/fuel maps are programmed to give “maximum” power on the LOP side, staying just outside the red box. This power is arbitrarily chosen, but I would choose just below LOP, for instance 25 degrees LOP, resulting in a relatively low speed loss.
ECON +, the ignition/fuel maps are programmed to give the maximum fuel efficiency. This power is also arbitrarily chosen, for instance 75 degrees LOP, resulting in minimum fuel flow, but accepting a much bigger speed loss.
Both Econ settings would be programmed with ROP values above 75% power and/or the ECU would automatically switch to the MAX PWR map when it sees power settings above 75%. This feature would make it literally foolproof, so you always have max power ROP available for take off and go around. Of course the LOP LED on the programmer should follow this auto switching.
Ability to have ”automatic” cylinder fuel trim for all power settings. During test flights we find what individual fuel trim is needed to have the EGT’s peak at the same time for several MAP and RPM combinations. This information is then “overlaid” on the ignition/fuel map so we get automatic individual fuel trim at these MAP/RPM settings with an interpolation between these points.

The new programmer will sit in a high visibility spot, so when not in program mode it can be used as an annunciator. It can show for instance the chosen power mode MAX PWR, ECON or ECON + and % power and AFR. When there is an anomaly this will be replaced by for instance ECU1 or ECU2, IGN1 or IGN2, FUEL PRESSURE, BUS1 xx V, or BUS2 xx V. The fault codes should be on a separate page. Ideally the white alphanumerics should change color to red or amber or alternatively the whole screen could change color from blue to amber or red. It is important to have a visible change otherwise it will be very easy to miss.
Also I find it important to see not only the LOP LED illuminated but also the power mode annunciation when LOP is chosen, again because a little LED will be overlooked very easily.
As far as the % power is concerned, I know there is no operational need for it and that often it is not very accurate. But with all the data available to the ECU you should be able to calculate a reasonable number and it is nice to have. As far as AFR is concerned, also no operational need, but it is a very nice indicator of your fuel efficiency. I plan on mostly using unleaded fuel so the Oxygen sensor should survive. Give the users some freedom to decide what they want to see on this page and everybody will be happy.

Gordon

We could turn off the A/B LEDs when a Fault is present, would make it stand out more.

We couldn't get any more traces crossed over past the LCD window to put more buttons on the left. Tried to shrink the height of this as much as possible to fit in the space above the stack. That was job 1. This is a production keypad so that is locked in now. Puts most used buttons closest to the pilot.

Mixture knob is still analog. After evaluation and having a digital knob years ago for one of our automotive clients, we feel analog is the best and quickest way to adjust mixture with EFI. The witness mark gives you immediate visual indication of where it is and in an emergency, nothing is faster than twisting a knob.

There really isn't a need in aircraft for different maps any more than in your car. The ECU can give best efficiency and power at all times, once properly programmed.

The EM-6 will have some new closed loop features for automatic mixture control on unleaded fuel. We don't feel that this can be used with leaded fuel at this time. If you'll use unleaded most of the time, I think you'll like what we plan to do for the closed loop control.

LOP would never be used in the pattern and there is software protection to prevent the extra advance from occurring above a certain MAP.

We'd have to add EGT sensing to do auto leaning outside of a wideband O2. Probably not in the cards within the time window to release this product but could be for the future if we can pull that data from the engine monitor.

We see that throttle angle can play a significant role in which cylinders peak first, even at the same MAP and RPM. It starts becoming more difficult to do this automatically and flawlessly.

We can flash the LCDs for better visibility of the fault codes and there are already 4 gauge modes to look at various parameters. The LCDs only have white alphanumerics.

AFR is already displayed in 2 gauge modes. % power is a good idea but like you say, too many variables to make very accurate. When it doesn't agree with the engine monitor, we'd get the phone call...:eek:

We currently have some pages and parameters user configurable and may do more of that on your advice here while keeping the device simple to understand. Too many pages or configurations becomes confusing eventually so there needs to be the proper mix of that we feel.

I know from the last 25 years in this business that we can't make everybody happy, but we do listen to the good ideas from others and if there is a large consensus, we'll work towards that.

Thank you for posting your thoughts here. It's given us a couple more good ideas to ponder.:)
 
Love the Design 1 - definitely will be going that direction with my airplane as soon as you've got it ready to ship. Keep me on the list and let me know...

Another big plus on the coming closed loop options for unleaded fuel - that's better than 90% of my operation, I'm interested in that.
 
Very relieved to see that a "standard" size option will be available as well. I do like the narrow stack layout but for all of us who can't redo their panel or don't have that spare space, we'll be able to drop it in the old hole. I like the LCD and buttons, also the LEDs. Closed loop is exciting, as I plan to use MOGAS as well for the majority of flying, at least when I can. I would challenge you to revise the documentation for the EM6. The manuals have a lot of information, but it seems disorganized and segmented. There should be just one big manual for each model with sections for 4cyl, 6 cyl, etc.

Really looking forward to getting mine flying next month and start tuning!
 
Very relieved to see that a "standard" size option will be available as well. I do like the narrow stack layout but for all of us who can't redo their panel or don't have that spare space, we'll be able to drop it in the old hole. I like the LCD and buttons, also the LEDs. Closed loop is exciting, as I plan to use MOGAS as well for the majority of flying, at least when I can. I would challenge you to revise the documentation for the EM6. The manuals have a lot of information, but it seems disorganized and segmented. There should be just one big manual for each model with sections for 4cyl, 6 cyl, etc.

Really looking forward to getting mine flying next month and start tuning!

The EM-6 documentation will be revised extensively.

Glad most people like the new programmer options.
 
Love the Design 1 - definitely will be going that direction with my airplane as soon as you've got it ready to ship. Keep me on the list and let me know...

Another big plus on the coming closed loop options for unleaded fuel - that's better than 90% of my operation, I'm interested in that.

The closed loop stuff will be standard on all EM-6 ECUs.
 
Design1 Programmer

We got a revised face plate back from the machine shop on Friday afternoon and did some test fitting to the prototype PCB. Everything is looking good so far.



You will need about 4 inches from the front panel to any other components forward for the data cables to clear.

We are on track to publish the face dimensions by early next week so folks can proceed with their panels.

Production PCBs for these should be on order by the end of that week. We are just making a couple more tweaks and refining some of the new code to operate these.

LCDs for production were ordered Friday as well. Getting excited to get these in production and getting on to Design2 work in earnest.
 
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Display Pic



Here is a photo of the prototype display/ keypad/ front bezel for the Design1 programmer. The LEDs, color and graphics format is similar to the CPI-2 programmer as we bring all our new products up to a common look and specs.
 
Looks great, Ross. I bet it's going to be much easier to read at an angle too. I have mine on the far side of the cockpit, so it's a bit of a challenge.

Really pumped about the closed loop option with the EM6 after learning more about tuning process! Real time/effort saver.
 
Really pumped about the closed loop option with the EM6 after learning more about tuning process! Real time/effort saver.

The closed loop option will eliminate a lot of the tuning time required but can only be reasonably implemented using unleaded fuels in our opinion, given the demonstrated variability on the lifespans of WB O2 sensors on leaded fuel to date.

So if you fly locally and haul mogas or can plan your trips to airports selling mogas or Swift fuels, this could be a good option. Whenever we get widespread unleaded avgas availability, closed loop will become the cat's meow for aircraft EFI.
 
Fault light

Ross, I really like your new programmer and look forward to implementing the EM-6 on my airplane.

For the fault light, do you provide a discrete output as well? I would prefer to have that fault also show up on my EFIS, which is a pretty simple task to implement if there is a discrete output available.
 
Ross, I really like your new programmer and look forward to implementing the EM-6 on my airplane.

For the fault light, do you provide a discrete output as well? I would prefer to have that fault also show up on my EFIS, which is a pretty simple task to implement if there is a discrete output available.

Thanks for the feedback. I expect that external output will remain for this purpose.
 
Design1 Programmer Panel Template

We have dimensions now for the Design1 panel cutout posted on our Aircraft Page for those who've been waiting (about 3/4 of the way down the page). I can also email that info if desired.
 
Ross - this is a great design. Any chance that you'll come out with a Design1 form factor controller for the CPI-2? I'm struggling having space for the existing controller in my new panel design for the RV-7A.
 
Not for some time, if ever. We made the CPI-2 one as small as possible and given the lower numbers sold plus time and cost to design and manufacture a second shape, it wouldn't make sense for us at this time. The CPI-2 delayed development of the EM-6 parts for at least a year so it's time to forge ahead now and get it done.
 
Spinoff Tech

I had a thought last night that perhaps the Design1 could be re-purposed with a new keypad for the CPI-2. This should only involve the cost of a new keypad which would only be a graphics change.

I'll investigate that with Barry and see if there are any other pitfalls in that idea. It still wouldn't happen too quickly as EM-6 stuff has priority but it would make it financially viable at least and speed the process considerably.

Thanks for the input David. Might be possible this way.
 
Progress

Design1 PCB files have gone to the PCB manufacturer this morning.

We are tweaking 2 small items on the enclosure and that should go to machining late this week for production parts.

Have a big box of LCDs and keypads in hand now.

New software for these completed and tested now.

Just have to wait for the production parts to come back to us now.

Design2 LCDs in hand now. Designing the PCBs and keypads should commence by the end of the week.
 
Design1 Programmer

Barry has just been finishing the software to drive the new Design1 programmer features.

Several people had asked if the LOP feature could still be activated with an external switch so we made selectable menus in the programmer to either use an external switch or the on-keypad switch. The answer is now yes.



Here is the screen configured for LOP keypad activation.

We'll have a few production Design1 programmers assembled next week for those who've asked for them and they will start going out with new EM-5 orders mid-month.

Again, we appreciate the input on what features people desire on the 6th gen system.
 
Mounting?

Hey Ross, color me confused here. How does it mount to the panel/radio stack? I see the front side mounting holes but is it designed to sit behind the panel, on top of the panel or is there some sort of bezel that attaches it?
 
Never mind...its hard to see the raised bezel on the programmer but once I put my glasses on it showed up. :)
 
The first three Design1 programmers shipped last week, 2 with new EM-5 orders and one to long time SDS customer and friend Rusty Crawford who is doing a panel upgrade on his 7A. Rusty is our high time Lycoming (Subaru previously) user with over 2000 flight hours who has given us lots of feedback and good ideas which have found their way into our new products.

Rusty, hope you will post a photo of your new panel.:)
 
I finally figured how to cut a nice, crisp round hole in Carbon Fiber to fit the old programmer in my panel.

Looks like I cut too soon.
 
I finally figured how to cut a nice, crisp round hole in Carbon Fiber to fit the old programmer in my panel.

Looks like I cut too soon.

Ditto. Fortunate for me it was just a AL blank...

Never buy anything until the last minute...something new or better always comes out...
 
I just received the new programmer, thing of beauty for sure.

And going to be much easier to mount in the panel than the round one was going to be.
 
I just received the new programmer, thing of beauty for sure.

And going to be much easier to mount in the panel than the round one was going to be.

I got mine a few weeks ago and I'm chomping at the bit to install it. I've got quite a bit of flying planned for the next couple weeks, and then I'm going to take my plane down for annual and start turning wrenches, including the SDS install.
 
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