rusefi.com

The first vehicle I'm setting RusEFI up on is my DD - a 92 Festiva with a 1.6L engine from a 93 Mazda 323.
Here's a picture from when I put it in a few months ago:



I have been very slowly playing with my STM as I can get some time.

So far I only have my STM board and a breadboarded version of the Hall input board as seen here: http://rusefi.com/forum/viewtopic.php?f=2&t=242

I'm running the latest version of the java console on my MacBook Air, and finally got things hooked up the other night to see what kind of signal I'm getting from the CPS. This is what I got: The tach value would jump around very fast and the signal was not very stable. So it does not seem to be the same signal as the aspire

First of I have to say you are in the elite club of less than 10 guys who has made it this far

On the digital sniffer we are interested in the first row of data. It is definitely not random, it's just that there is a bit of noise. I really hope that all it needs is a capacitor, like a "103" - 0.01 uF - capacitor between the signal wire and GND either on op-amp input or op-amp output side. Is there any chance you have any capacitor to give it a try?

I will point our EE expect to this thread, can you post a picture of your breadboard setup?

I put a 103 cap between signal and gnd. The values seemed to dance around slightly less, but it still said "noise" frequently. So I tried a 105 cap and I no longer got the "noise" value but it fluctuated a lot between ~200-4000. The range of numbers would increase if I revved the engine.

Here's the setup: and another screen shot from this afternoon:
Also, I'm pretty sure this is an optical position sensor. However the disty feeds the ICM and I'm getting the output from the ICM. I can take a spare dist apart tomorrow if it would be helpful.

Do not destroy a spare dizzy, no point in that. What you can do is take the spare distributor and play with it on a bench? That's if you have a piece of harness to power it up that's if you have a power supply because I think it might want 12v.


This is probably asking to update the firmware but I do not think there were any bugfixes related to trigger input.

I hate electronics It's still some kind of noise. Next thing to try would be a pull-up resistor - so, a resistor between op-amp input and 5v. 1K to 10K, do you have anything?

I think it says Firmware N/A because I had already unplugged the board when I took the screen shot.

Taking a disty apart doesn't mean it will be destroyed But if something did happen to it, well I probably have 1 or 10 around here somewhere

I have a few hundred resistors and caps of an assortment of values. I will try a pull-up resistor and I'm going to dig around a little more to see what I can find out about the signal from the distributor. I need a scope!

skeeters_keeper wrote:I think it says Firmware N/A because I had already unplugged the board when I took the screen shot.

I am not sure it works like that... But it could
What does 'hello' command say?

it might be you just need a shielded cable instead of those caps?

puff wrote:it might be you just need a shielded cable instead of those caps?

My setup runs on long & ugly wires with ten lame connectors along the way, and it's fine. I believe OEM only uses shielded wires for knock sensors.

wiring to crank posiion sensors is also shielded. your ignition system might be less noisy thanks to resistance in your plugs and plug cables.

Good progress.

Lets see if I'm understanding the above picture with the laptop correctly. I see only one green wire that leaves the picture. I'm assuming this is your hall/CAS signal. However I don't see a black wire connecting the STM GND to the vehicle - battery terminal. With out the - reference, I would expect much more noise. Can you add a black wire from the battery - to the bread board black wire.

Also to help minimize potential issues, I would suggest using the laptop on its battery if possible instead of being plugged into the wall. It looks like you are doing that, but figured I'd make sure that was on purpose instead of by luck.

What is the voltage you get from your signal wire? Is it above 5V? I might also suggest using a 2k to 5k in series with your green signal wire. Some op-amps have diodes on the input signals that will dump current to the signal pin exceed the + rail pin. This resistor will limit the current dumped if the op-amp happens to have this diode, and if you happen to have more voltage on the the op-amp input signal ping relative to the op-amp + rail pin.

kb1gtt wrote:However I don't see a black wire connecting the STM GND to the vehicle - battery terminal.

If that's the case then it would explain a lot. Nice catch! If that's a catch

Indeed, I did not have a ground to the battery!

After some more messing around, adding a ground to the battery and a resistor inline with the signal (which is 5v btw) this is what I have at a fast idle:
And with the engine revved a bit: And here is what the stock festiva disty looks like inside: Oh, and Russian it still says firmware NA - so I guess I need to update my firmware on the board

My Mozilla does like your .tiff images. As in cannot show them

Update: my Explorer was able to show them. Can you please zoom in so that it shows say 6 waves? Anyway, that's some real progress here!
I still see some noise - these lines inside the waves - but we are close.
I have to step see if my Festiva would fire up with a 2000 Miata head, ttyl. Let's thank Jared for the GND hint

PS: looking at this dizzy I see a two channel signal, do you have another wire? Can you hoop up the secondary channel the same (your op-amp is probably dual-channel anyway) and I will need your log files to figure out the exact trigger shape. Good progress!

PPS: on another thread you were concerned about boards getting obsolete. They do not get obsolete - you can still use the older individual modules, the firmware would always support them.

For cartoon like pictures, I would like to suggest .png it will have good compression while keeping a good level of detail and pretty much everything can view it. When it comes to pictures from a camera or similar with many different shades of color, I would suggest a .jpg, it's a lossy compression, but generally good enough as your eye will blend things together. I also can not see the .tiff on my linux Chrome. I'll go look at them with a windows machine and IE, but there are sure to be others with the same problem.

I'm also likely a culprit about creating a feeling like things might go obsolete. I'll always push for changes as I tend to feel things can always be better. It has been working well here as russian has been drawing lines in the sand and making things usable. Getting boards now should work with your setup and I don't see them ever being obsolete.

Oh, also what op-amp did you use? If you need some help getting this working on the second channel, I can offer some help, perhaps a pencil sketch or something like that. Let me know if you need a sketch.

Didn't know it was tiff - works okay in my Safari on a Mac

rpm figures are so nice!

Sorry about the .tiff, that's what Grab (the screen capture program) defaults to. I usually convert them to jpg but got lazy this time...

I am using an OPA2340, but I also have a few MCP6002 as discussed in the "DIY Hall input" thread.

A pencil sketch of using two channels would be great - would the second channel feed another input pin on the stm?


As far as boards going obsolete - I'm not saying that they aren't still functional, but they are no longer necessary if you have the frankenstein board. So the time/money spent on them was basically a "waste" because you're no longer using them once you have a newer version of the board. Similarly V.1 of frank may work but I'm sure it will have room for a few improvements, maybe integrated BT or power supply etc, so if I buy it now and you release v.2 in a few weeks... well, you see what I'm saying. I realize things will always change and you can't wait forever for the "final" version because with tech there is no such thing, but I'm sure this is a large part of the reason you aren't seeing more people buy the boards right away.
I do plan to order the board in the next few weeks... I just spent too much $$$ on my rocketry hobby this month!

The sensor has a 4 pin plug with only three wires, 12v, gnd, sig.

I was hopeful that the other pin was there and ready to be used - so I tore the disty apart a bit further and there is nothing on the other pin :/ only one LED and it is inline with the four smaller slots, the spot for the other LED (in line with the one slot per revolution) is empty. Since this car is batch fire from the factory I guess they didn't need to know which cyl it was on.
So if I understand correctly that means there isn't enough information for COP or sequential injection and I'll need to either add a trigger wheel on the crank or maybe fit an aspire distributor, which has both signals.

installing trigger wheel on the crankshaft won't provide you such information, but will probably increase accuracy?
so do both, and request a feature, so that close circuits in the disty give signals for a certain sparks for instant start

oh, it's probably contactless. one more option is to fit your own, custom-cut slotted plate, with, say, 7 usual size slots an one twice as larger slot for 0º.
one more thing, which I can't understand is that on the upper screenshot you have somewhat 6 impulse per rotation, and on the lower screenshot, with increased rpm you have a different number of impulses? weird.

Ah 5V, with a J927 optical sensor. Hmmmm, why can't I find a pin out or schematic for this sensor? Is there a snippet from a service manual or something that could help?

Looks like the noise is consistently on the falling edge. I think I know why this is, but I'm trying to find a reference schematic. Do you know if the sensor's internal wiring is similar to this http://m.eet.com/media/1093612/0307feat2fig2.gif

If so do you know what the internal pull up resistor is? I think it is done that way, and if it is, I would suggest a 2k to 5k resistor between the green signal wire and black GND. That will probably fix the issue, if not, I have some other suggestions, but lets try that one first as it's easiest.

btw, for positioning purposes you could just install a photon-coupled transistor against the larger inner slot.

Here are two more shots of the sensor from the distributor. I found some info in one of my books on the CPS: It sounds like the BP (1.8DOHC) should have a similar/same sensor but with both LEDs - great, I have one on an engine stand!

Would be funny if a piece of an Aspire dizzy would bolt on - http://rusefi.com/articles/tachometer/1995_aspire_distributor_3.jpg

So, what do you we call your engine configuration file? Mazda 323?

Here it is:
and inside: No such luck :/

This one is a Mazda BP. I have another BP in a car outside - from an Escort GT, so maybe that one is optical. However I ran out of daylight. Even if it is optical I'm not sure I need the second sensor yet... but still, it'll be interesting to see if I can get it from an escort disty.



I'm not sure if any of that info helps you know whats going on inside my sensor, and I didn't try it with the resistor between the signal and gnd yet. Hopefully I can try it tomorrow night because I'm going to be gone most of the day tomorrow.

russian wrote:Would be funny if a piece of an Aspire dizzy would bolt on - http://rusefi.com/articles/tachometer/1995_aspire_distributor_3.jpg

An aspire dizzy will bolt on! I don't have one right now unfortunately... I did last week. But I don't think my mazda ECU will like it and I need to keep this car on the road :p

russian wrote:So, what do you we call your engine configuration file? Mazda 323?

90-93 Festiva (1.3l SOHC) and 90-94 mazda 323 (1.6l SOHC) use the same general engine management. Meaning, you can run the 323 engine on a Festiva ECU. The distributors are the same part number, VAF can be interchanged (although the 323 VAF is slightly different) etc. Almost exactly the same engine just one is bored out a bit. Some people have run their B6 in a festiva on festiva ECU for years.

So I think you can call it either Festiva or 323, because with a small amount of tweaking it will work for either.