MS Adapterboard Anyone???
 

I've been toying around with the idea of creating a MS adapter board, and I'd like to see if there is any interest here.

The board would have a place to solder the big yellow 64 pin connector a place for a DB37 connector and holes for soldering wire that go to the original ECU. Effectively this would be a breakout board for the ECU and MS signals, and it would also make it much easier to build the harness. The board would be silkscreened with easy to read labels of where all of the signals are. The board would work with both boomslang and standalone setups.

This would simplify the harness building procedure which I found to be the most tedious part of the whole process. Cost will depend upon my production costs, but at the moment I'm guessing boards would cost about $30 a piece.

Let me know what you guys think. I'm currently working on the 1.6L board, but once I get it done the other models should follow shortly.

I'll post some screen shots of the board once I get it done.

I can't picture it.

He's talking about making something like this:

http://megaefi.com/

Would make MS install a snap really.

Ok so, I'm at a point that I have something to show you guys.
I'm not done with it yet. I think I'm going to add some proto area as well as clean up the silkscreen. Its hard to see whats really going on because I can't get the copper pour to turn off, but I took all the knowledge from the harness portion of the DIY MS thread and put it onto a board which should make everyone life easier when it comes to making the harness.

http://img405.imageshack.us/img405/2...taboardcq8.jpg

Interesting concept.

I'd suggest that you might want to beef up the size of the traces carrying the two INJ signals, those are pretty high current lines. Ditto the IAC valve.

Like I said this is just preliminary. I'm going to beef up several of the traces, bring out and label all the DB37 pins. Hell if I get adventurous, I might add a circuit for the fans and AC (which would practically make a DIY MS a PNP). If I get some of these made would any of you be interested in purchasing one???


Don't forget I also intend to make a couple more of these for the later models.

If you buy an MSPNP you get one of those for free you know! ;)

I'm aware of this...

a) I'm a computer engineer and this is "fun" for me
b) MSPNP's are $600+, not that I don't like DIYautotune, but that seems a little steep. I could easily put a kit together and sell it for under $100. This would effectively bring the price down to $300 ($200 for DIY MS kit $100 for my kit). I don't know about you, but I'm a poor college student and I would much rather pay $300 for a plug and play solution than 600. Also this would not be completely plug and play. Soldering would still be required. This would effectively create a DIY MSPNP for about half the cost.


Not to mention, this is going to help me pay for my turbo this summer.

hmmm, sounds interesting. I would like to play guinea pig with this.

Guinnea pig line-up
 

I can't squeal like a pig, but I'd be up to try this out as well. It sounds like a great product, especially if it can be used as a standalone on a car with AC. I'm also going to go with a T3 once I get MS, injectors and Wideband sorted out. See, some of us really do take the advice on this forum to heart.
Best Always
Alden

Sounds like an awesome project to me. If I can help let me know. You'll need different board for 90-93, 94-95, and 96-97 but that's no big deal.
As for NB's unless we can come up with a A/C circuit as well as a alternator circuit (or use Abe's external regulator idea) it will be much more difficult to do this. You could even fab it up so that it could mount to the screw holes on the MS case end plate, possibly using a plastic bottom for some extra strength. Letting it plug directly into the MS.
One easy option for the NBs would be to actually remove the pins from the female connectors that go to the stock ECU for the Fuel injectors and the Ignition coils. Then run the to their own male connector. You could utilize any one of the production boards this way because you could put the pins in any slot you wanted.

Man, what an idea. You do your own screen printing or etching?


EDIT: I like the idea of just pulling the wires out like that and putting them in a new connector so much I think i'm going to do that to my own car. That removes like 55 points of possible failure by removing the boomslang.
It would suck not using the stock ECU grounding anymore but that can be resolved some other way. hmm

Edit 2: Got ahead of myself, went off and forgot about tapping CLT and TPS. Lame. Not a good idea if you want to retain OBD2 compliance like you do with the boomslang. Darn.

Edit 3: That too wouldn't be a big deal. CLT, IAT, and two ground wires could also be pulled from the stock ECU connector, installed the other connector. Then Y off the back of the male connector like we do with the current boomslangs and run those back to the stock ECU.
It sounds messy, but i guarantee the 4 Y'd wires is much cleaner than the 64 wires for a NB boomslang plus the 3 wires for CAS, 1 wire for IAT blah blah blah.

Thanks for all the replies. Sadly no, I don't do my own printing or etching, but I do have access to board mills at my school that I can make prototypes on at a much lower cost.

I'll be starting with the 90-93 because thats what I care about most/own.
I need to do some more research on the NA's AC and Fan sytem, but it shouldn't be too hard to whip something up to take care of that.


As for the NB stuff:
I'm not familiar with it near as much as I am with the NA. I've hear about the alternator, but not in detail. I guarentee you though, if the stock ECU makes it work I can find a way to make it work (or I think I can). Also the AC shouldn't be too bad. My guess is that there is effectively some kind of thermostat circuit that engauges and disengauges the AC clutch based on evaporator temperature. I could whip up something like that with opamps in a heatbeat.

I'm not familar with OBDII, but it seems like there would be a way we could fake that signal. If the stock ECU makes OBDII codes why couldn't we. This might add a microprocessor onto the board, but embedded stuff like that is really my specialty.

The fan system is dead-easy.

The primary cooling fan relay comes to the ECU at position 1R, a Black / Green wire. If you pull this pin to ground, the primary fan turns on. Note that a relay modkit is required on the MS itself, it can be driven by either JS0 or LED15 (warmup), and there is no standard as to which DB37 pin it comes out on- so this needs to be set in stone beforehand.


A/C requires no work on the part of the MS, just some creativity. When the A/C button is depressed and the interior blower switched on, the climate control panel gives the ECU a closure to ground on position 1Q. Use this closure to drive a relay which provides a closure to ground on position 1J, a Blue / Black wire. The energizes the A/C relay, which turns on the second fan and also powers the magnetic clutch on the compressor. Actually, a relay might not even be necessary- you could probably just loop the two pins.

Although it would sell like hotcakes, the big problem is that this is specifically prohibited by Federal law. Also, the stock ECU, in addition to transmitting the "all clear" message, is theoretically capable of stating its VIN number. I don't know if this feature is currently being exploited, but it's a potential gotcha.

Not sure if you've already got a PCB vendor in mind, but for this kind of thing I use expresspcb.com. They're cheap, they're fast, and the boards are really super high quality- they will do everything from uncoated double-sided (with thru-plated holes) to four-layer with soldermask and silkscreen.

Psshhhh illegal....
Freaking laws, I should be able to do whatever I want with the hardware I own, but I digress.

I'll keep working on the 90-93 board and I'll keep you updated as to my progress. Not sure how much I'll get done in the next week or two. This weekend I'm going to Chicago and we'll next weekend is a holiday...

As much as it pains me to say it, the laws are there for a reason. While I don't necessarily agree with the decision, I understand the reasoning behind it.

So I was bored and looking at the NB schematics for the charging circuit (page 27 in the 99 wiring diagram PDF). What is the deal with the alternator nonsense. I'm guessing the problem is with this powertrain control module?? If thats not it, I'm not sure how the ECU has anything to do with the power system of the car. Could someone elaborate more on the problem with NB alternator's and MS? I should be able to devise a solution if I know more about what is going on with that.

I've got to go to class :( but I'm going to take a look at the NB A/C later today.

Good idea! ;)

Basic alternator theory:

The voltage produced by the alternator is a function of the voltage applied to the field coil winding. Applying a higher voltage to the field coil causes the voltage output of the primary windings to increase.

Traditionally, most alternators have either used an internal voltage regulator, or a simple external regulator. The regulator looks at what the "system" voltage is (the voltage actually coming out of the alternator) and either raises or lowers the excitation voltage to adjust it.

Some newer cars use the PCM as the voltage regulator. NBs fall into this category, as do many Toyotas. Apparently, the PCM takes certain other factors, such as temperature, into account in making the determination as to what the alternator voltage should be. See this diagram, taken from the 2000 Miata wiring diagram, section A, page Z-16:

http://img261.imageshack.us/img261/387/altxp7.gif

The wire coming out of the middle of the rectifier stack and going to reference (6) is a "sample" of the voltage coming out of one winding of the primary coil going to the PCM. I don't know why they chose this particular location- it's quite possible that the PCM also monitors the "raw" +12 coming into it.

The PCM then outputs a voltage on pin 1T, which comes into this picture at ref (5). That voltage is what drives the field coil, and determines what voltage the alternator will produce. (actually, I question that picture- the way that PNP transistor is shown, it can't possibly do anything. I think it's supposed to be an NPN)


The "problem" is that there is no mechanism on the MS, either hardware or software, to produce a variable output voltage based upon input voltage.

The solution that Abe came up with to run his stock NB alternator on a standalone MS was to locate an external voltage regulator from some GM or Chrysler car that was more or less compatible with the NB alternator's requirements, and he installed that to drive the wire that controls the field intensity. In theory, once the characteristics of the field control circuit are known (a plot of control voltage vs. output voltage) it should be possible to design a simple op-amp based circuit to perform this task.

Once you have the schematics finalized. I should be able to get them stamped...

So from reading this it would seem there is no actual regulator on the output voltage of the alternator. If this is the case, this is really super easy to do.

I completely agree on the opamps. I'm pretty sure I can whip something up that will automatically adjust the control voltage using negative feedback. Then we won't need to know the field voltage/reference voltage relationship, the opamp should magically take care of everything.

I took a quick look at the NB A/C and it shouldn't be that bad, maybe some comparators and a few transistors and I can get it working.

On a side note, are there any other EE/CPE's around here??

Uhm, can you imagine what a 70A linear regulator stuck to the side of the alternator would look like? :rolleyes:

Every automotive alternator I've seen was "regulated" by a feedback mechanism- adjusting the field coil intensity to achieve the desired output- rather than what we'd consider a true series regulator- it's hugely more efficient, and sufficiently accurate for the degree of precision required. It's just that the controller for said mechanism is usually either internal to the alternator or, at most, a small external box. This business of having the PCM do it is relatively new, and I cannot for the life of me figure out why the PCM cares how warm it is outside, unless they're trying to eke an extra 0.01% out of the battery or something...


I don't think it'd be any harder than the NA A/C. If you've got a '99-'00 diagram in front of you, take the LG/B wire coming from the pressure switch after the "A/C Amplifier" that goes to 1P, gate it with an output that goes true when TPS = WOT, and use it to control either a DPST relay or a pair of open-collector NPNs that ground the "A/C Relay" (L/B wire at 1S) and the "Condenser Fan Relay" (L/W wire at 1I). I freely release that concept to the public domain for all uses commercial or non-commercial.


Technically, I'm not a EE. 100% hands-on training. Started working at a radio station when I was 16 years old- you learn really fast when you're working on a device with filter caps the size of your leg, vacuum tubes that weigh 20 lbs and measure 10" in diameter, and front-panel meters scaled in kV and 100s of amps (though not on the same circuit, thankfully).

I'd be more than happy to test out one of these boards for a 94/95 for ya.

Those caps and tubes sound exciting, thats something I've always been interested in but never gotten a chance to mess with. Although next year for my senior design project I think my department is going to let my team build a continuous wave audio modulated tesla coil. Should be a good time.

As for the regulator, I was sure it wouldn't be linear, but thought there might be some switching regulator of some sort. (I'm a computer engineer and I have been exposed to much power stuff)



As for every one who has volunteered to be guinea pigs, I'm doing the 90-93 first cause thats what I have and I will test it myself and maybe on one turbo car. Then I think I'll try to tackle the NB's cause DIY doesn't have a solution for ya'll and I think it would be mildly humorous to beat them to a semi-plug and play solution for the NB's. I will definitely need volunteers for this. The rest will be last. I'm in Terre Haute, Indiana. I would prefer volunteers to be semi close by.

Lets not get ahead of ourselves though, I'm really busy with school so this will be done in what little spare time I have.

Hondas have the only ECU-controlled regulator I've been able to study in depth so far. They did this not for the battery but for fuel economy. Honda set up their ECU so it would drop the alternator output from 14.something volts to the 12's during cranking and under certain cruising conditions.

Like I said, I should have the ability to get the circuit boards printed on the cheap...

Something I'd suggest would be to put all the outputs to the 16 pin connector, like the fuel pump, o2, AIC outputs, spares, etc. This way if anyone build custom circuits like (knock or ebc) they just use a plug to simply plug them into the connector and not have wires all over the place...

a few things may want to be in two locations, like the 02 / WB signal....

Toyota is doing it as well, at least on the Sienna. Discovered this fact while helping a friend install a trailer connection on one to power & recharge a camper.

Although nearly all AM transmitters are solid-state nowadays (and some of them are actually direct digital synthesized- no linear amps at all), high-power FM transmitters are surprisingly primitive. Up until the mid '90s, pretty much all of them were tube-based, mostly big ceramic ones like the 4CX and 5CX series. Even today, the biggest solid-state model that we build is a 10 kilowatt, and it uses about a hundred discrete power amps packed into 16 modular blocks. That particular model (the Z10-CD) runs the PA at about 48-52VDC, and uses multi-tap transformers rather than any kind of direct regulation.

The big FM transmitters, everything from 20 to 70 kilowatts, still use good old-fashioned pentodes and tetrodes in their final amps, though most of the IPAs (the drivers) have gone solid-state.

The first transmitter I ever worked on was a Harris FM20K. It used a 4CX15000A final tube, which ran at about 9.45 kV on the plate. The filament circuit drew about 160A at 6.1 - 6.2 volts, and that was not even the biggest tube in that family. The mega-VHF rigs use a 4CV100,000 tube- 17.5 kV @ 16A, with a 215A @ 15.5V filament.

And the UHF transmitters are even freakier. Most of 'em use either Klystrons or IOTs- yeah, the same stuff they build linear particle accelerators out of. Pure inductive devices with magnetically focused beamlines- we're talking 50 to 100 kV, and they're water-cooled!

[/hijack]

"4CV100,000 tube- 17.5 kV @ 16A, with a 215A @ 15.5V filament."

That is amazing. I want power supplies that can do that. :eek5:

Here's a guy who offers something similar for motorcycles:

http://turbobikes.org/forum/index.php/topic,175.0.html

Maybe we all can take this one step further and include all the MS hardware onto the same board? So we dont have a mass of wires (and the corresponding number of failure modes) sticking out from the board? I dont know the legal issues involved in this though, but MS being open source they should have no problem?

Or, alternatively, stack the adapter board on top of the v3.0 board using the DB37, and mount the whole thing in a bigger case.

That is exactly what I was talking about in the "Rev 4.0" thread. Make one board that had both the MS itself, plus all the "mod" hardware that normally winds up being a mess of jumper wires.

As to "legal issues", that's the sticking point. The Extra code is open-source, but the 3.0 schematic and board layout are copyrighted B&G. I have not approached them (since quite honestly I don't have time to do this myself) but I wonder what their response might be?

I think taking their schematics and redo'ing it specifically for the miata would be legit because we would only use their schematics for reference. I'm pretty sure that isn't illegal.

This however is not what I will be doing. It seems you guys are complaining about the jumpers and resistors we have to add to the MS. Its like 4 wires, how hard can it be. What I aim to do with my board is effectively replace the wiring harness (which has like ~50000 wires to screw up on). Making a new MS is definitely doable, but I don't think I want to tackle it.

If anyone is interested though I do have a footprint for the yellow female ECU connector in an orcad library file (*.olb), and let me say you should be very thankful for it cause making the footprint was a bitch. PM me with an email address if you want it.

Also I'm honing in on a final design for the 90-93 board. I'm going to mill a prototype next week and test it on the car as soon as possible.

Finally I think I figured out why my MS isn't working. Originally I was trying to get it to run with the stock AFM until I got my intake drilled and tapped. The car ran once before I got the GM IAT in. Then I switched to the GM IAT (WITHOUT RUNNING THE FUEL PUMP WIRE). The car would fire up, but would always die (because it wasn't getting fuel). Well after looking through all these schematics it is now clear to me. I'm pretty sure my maps are close to correct (and its warm outside so no coldstart to deal with), so hopefully I will finally be megasquirted tonight!!! I can't wait!

at least comment on my "can get them printed on the cheap" comment..... :(

No, I don't have a board place. I've been looking around online, but they are all pretty expensive. The only capability I have is 2 sided small-medium sized boards not silk screen or solder masked. This is enough for testing out the design to make sure the layout is good and everything works. The only thing I pay is the cost of the blank copper board itself.

If you have a good board place for cheap, I am definitely interested. The final board will need to be 2 side silk screened and solder masked.

I'm going to keep it small (no proto area on actual adapter), but I'll bring all the signals out on a pin header. Then we can make a board will a female header bring out the signals and have a proto area on it. We can have that header common to all the adapters so that "mods" are interchangeable.

Finally, I turned on the fuel pump using the diagnostic connector and sure it enough it fired up and ran this time!!! I should be running on the MS using my boomslang by the end of the weekend!

tell me exactly how it needs to be printed and ill see (IE, dad is general manager at a plant that makes telecommunications circuit boards)

Uhm... when I get back home I'll find a picture of the backside of my MS. It's a forest of green wire.

Mine is nuts too and i'm about to add EGT and shift light to it.....

http://www.jugrnot.com/megasquirt/CRW_9254-1.jpg
http://www.jugrnot.com/megasquirt/CRW_9255-1.jpg

4 jumper wires my ass...

I gotz mo wirez than yall:

http://img187.imageshack.us/img187/654/dsc00345fu9.jpg

I'll defiantly admit yours is much much cooler than mine! :) I'm only using the stock case for my boomslang harness..

http://www.jugrnot.com/IMG_0326.jpg

Rose Hulman or ISU?

I meant the 4 wires that required on the backside not all the extra mods that are optional. But yeah, a whole new MS specially designed for the miata sounds alot like a MSPNP with a proto area...

AND
I go to Rose. (stop reading here if you don't care) Which none of you have heard of, but it's actually a top ranked engineering school. For those younger forums members (if there are any), it's the best school you can go to if you are really serious about being good at what you do (much better than PurDON'T). www.rose-hulman.edu

This sounds like a very interesting concept especially if you include the A/C circuit

It seems like the hot side of the fuel pump is switched by some relay somewhere which is triggered by the ignition. The ground side is switched by the AFM. It seems to me that an easier solution than tapping the FP wire under the dash and having the MS switch it would be to just jump the fuel pump on the diagnostic connector, so its always on when the ignition is hot.

Is there a reason I shouldn't do this?? (I can't think of any)

http://www.boostedmiata.com/technical/fuel_control.jpg

http://www.boostedmiata.com/technical/FuelPump.gif


Diy was able to do something to get it working....im too stupid to understand what it is.

I figured out how to do the fuel pump from from the ECU connector!!! (for NA's)

DIY removes the ST SIGN fuse from under the hood which isolates the circuit opening relay from the starter. There are two coils in that relay one of which has a connection to the ECU. The one that normally turns on the fuel pump doesn't, but we can just use the other one. Then everything will be happy.

Can you explain that for me...

i see two inputs on the lower coil: one from the starter and one from the ecu (1c) both positive. Then the positive to the other coil from the ecu (1B) and AFM the ground.

The MS grounds the signal right? So you remove the fuse to prevent battery from seeing the MS circuit...then what, the bottom coil has two grounds then, and the second coil has a positive and missing a ground from the AFM....dont' see how that will trigger the solenoid.

I am very interested this, as I plan on going MS DIY myself soon (within a year), however have just started my journey, still have a lot of reading to do. I also have a 1996 so my car could be a good candidate for an OBDII board.

BTW, you asked if anybody in here is an EE. Well, I am, but I am sure I am not the only one.

You don't ground the other side of the bottom coil, you give it 12V from the ECU. The current will travel from the ecu (through a resistor), through the coil and out to ground. This should turn on the fuel pump.

I think the OBDII plan has been nixed due to to legal issues, plus I don't really care about it since I have a 91. It probably wouldn't be that hard to implement. Its just a special serial protocol. Chips exist that convert RS-232 to OBDII and vice versa. There is a lot of information available if you are interested, just google it.

Hey Brain,
Looking at the first pic you posted, it appears the ecu needs to pull the STA circuit high (pull up circuit in the MS) via the 'V' labelled trace with teh 11 in the circle.
You would then need to remove the STA fuse so it doesn't blow if the MS grounds the connection (for example if you are flashing the ECU).

Cheers
Nuno

Well, here we are, the pictures. Yes, I am a little embarrassed about how messy everything is on the backside.

http://img120.imageshack.us/img120/3...ontsidevp5.jpg

http://img120.imageshack.us/img120/7720/backsidepf5.jpg

That is why I'm so fired up about building a new mainboard...


Well, the mods that you see on my board are:

1- The "usual" twin spark outputs, with 100 ohm pullup instead of 1k.
2- Abe's dual comparator circuit for CKP and CMP input.
3- PWM idle
4- Relay driver for fan
5- Baro MAP
6- Knock input
7- Table switching input
8- PWM driver for EBC
9- Relay driver and PWM driver for WI

Of these, #1 thru #4 are absolutely necessary for operation, and I consider #5 thru #7 to be almost essential as well, in terms of making the MS equivalent to a "real" ECU. #8 could be considered "optional", and #9 is really the only one that I'd consider superfluous.

Observant observers will note that there is one dead wire on the board- it's got a pullup resistor on one end, and the other is cut an goes nowhere. This was part of the old trigger input, and I forgot to remove it completely.


Safety.

Now, I admit that when I was using an EMU and I removed my AFM, I jumpered the fuel pump on. The point of having it controlled by the ECU is that if you get in a crash, assuming the engine stalls then the fuel pump will shut off. You don't want to be in a severe front end collision that ruptures the fuel system and have the fuel pump happily continue to empty the entire contents of the tank out into the engine compartment.

On a 1.6 you have two options. You can tap the wire that goes from the AFM to the COR and provide it a closure to ground. This allows you to use the "stock" MS fuel pump driver circuit. Or, you could invert the circuit (making it a +12 active-high output) and connect it to pin 1C of the ECU, which is technically supposed to be the Start Signal input. This is how DIy does it, and as yertnamreg1218 points out, it's why you have to pull the ST SIGN fuse.

The one that goes to the ECU 1c is, in stock form, an input to the ECU, not an output from it. It tells the ECU that the starter is running.

No, it pulls it up to +12. The other coil in the relay goes totally unused.

yertnamreg1218, I've hijacked your thread, and I apologize for that. I'll take this back over to my 4.0 thread.

duh, wtf I'm stupid.

I like the hijacks they add flavor and culture to the thread. Not to mention I like talking all this stuff out before I go designing something. I'd prefer it to work the first time.

Joe I take back my earlier comments about wiring the MS, you win...(damn that is alot of wires)

I don't think I've heard about the comparator circuit for the CMP and CKP. Could someone enlighten me.

More and more I think you are right about a total redesign...

I just finished up the 90-93 schematic for the board. Its not everything you guys asked for, but it will make the install a whole lot easier than a DIY and approx $200 cheaper than a PNP. I still have to layout the board, but that shouldn't take to long because I only added a few components from the first layout I did. I'll get this board prototyped probably by the end of the week and I'll let you know how it works out.

The layout is done and the I've handed off the gerber files. The guys at school will probably do the board at night so they don't have to listen to the mill, so assuming they start it tonight (and do a side a night). I should get the board back in my hands thursday or friday. Assuming I get the connectors in by then I should be running on the prototype by this weekend.

Here are the final specs on the 90-93 board:

approx 3"x5"
Fuel Pump fix
AC fix
Fans mod
EBC

No proto area, but all signals are brought out the MS connector and the important ones are brought out of the ECU connector to breakout points.

Here is a picture of the layout:
http://img178.imageshack.us/img178/2...taboardet0.jpg

Got a schematic for that we could see? My eyes hurt from trying to follow all the traces in that proof.

umm already been done...

http://tuner-deals.com/index.php?mai...b1ce704d15223c

Closeout price is nice

Edit: but the connector looks different in the purchase website. The right connector was pictured on msextra
http://www.msextra.com/viewtopic.php?t=27404

Edit (again) found it witht he miata connector
http://tuner-deals.com/index.php?mai...b1ce704d15223c

I have a schematic, and would be happy to post it. However, my computer shit all over itself last night. It tries to boot, bsod's for a fraction of a second then reboots. Sadly all the miata stuff I've been working on is on that computer. Our IT people at school are fixing it, and I should have it back soon. I'll post it when I get back.

Ampz,

I hadn't seen those before. Those are nice, but its still not a great solution. The board I'm building will plug in directly to the megasquirt (or using a standard DB37 cable), and the car's wiring harness. All you have to do is solder on the components and plug it in.

Hope you work on the 99-00 after you get this one working. You'd have a real chance to hit a sweet spot in an underserved market (beat DIY to the punch). Currently, 90-97 have plenty of options for relatively cheap solutions with MS and others.

Hope your computer problem is solved quickly. Minimally, I hope you can salvage the data on your hard disk!