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The simplest solution is to use an external igniter, the current set up is going to very prone to issues and increasing the spark voltage will increase the spikes on the primary side until the output driver clamps at around 450V. Have you tried separating out the ignition wires from the rest of the ...

The module arrived this afternoon, it doesn't use a CJ125, I must have misread that somewhere. The main micro is a PIC16F1716 and it also has a PIC12F1840 and a 78L05 regulator. It came with some nice paperwork and a shiny sticker but without any ESD packaging which is a big concern.

I expect that its simply a CJ125 with a small microcontroller as the interface, there is no need for a PSoC.

No progress on this for a while but I am attending the ST workshop for the STM32L4 devices this Wednesday.

I will do. The CJ125 was used on OEM ECUs at the last place that I worked, I wasn't the designer for that although I recall that there were some issues with a lack of decent documentation. With a working unit and a protocol analyser it should be a breeze.

russian wrote:http://www.wide-band.com/product-p/apsx_d1diy.htm

It looks a bit homemade but at that price I bought one anyone to play with. I also have an old kit from 14point7.com (not 17point7!), I forget which version.

The CJ125 solution is the most straightforward although I seem to recall that there is a more modern version of that chip.

Averaging is a low-pass filter, you can either increase the number of samples or reduce the sample rate. If you are average over 0.8secs then it should be fairly stable, its possible that you have a noise issue on the ADC.
Edit: Looking at that data I don't see what the issue is.

I have seen a number of similar issues with grounds on the CANBus, laptop power supplies can cause big problems when they are plugged into the mains supply and running a ground wire between the laptop and the ECU is highly recommended, if you can then always run the laptop from its internal battery....

There is a useful guide to PCB design on the Ford-EMC pages. The flexi-terminal caps aren't designed to cope with vibration but with thermal cycling, they are generally used on larger packages and on permanently powered circuits to prevent short circuits due to cracking and the subsequent fire risk....

regarding schemes with a charge from the ignition coil - capacitor is quickly discharged and will not give an accurate picture of the ION current. to get a beautiful picture need a current mirror with external power. I've used the Woodward coil in an OEM application, I believe the newer Harleys use...

TI recently updated the TPIC8101 datasheet. One of the lines that is interesting states: "For a flat-type knock sensor, the bandpass filter design equation can be used to determine where the center frequency should be set." Following that, they give the standard DSP biquad filter equation...

Well, it's depressing how much has to be done to have a useful project. In my experience a new OEM ECU usually takes a small team 2 years, 1 year to produce and qualify the ECU and 1 year for the vehicle manufacturer to do their stuff. A full qualification validation followed by a full product vali...

I should also point out that the RF caps provide ESD protection as well. Typically you would be looking at something like 330pF, 8kV or 15kV discharged through a series resistor (1.5k?). A 33nF cap will give a voltage attenuation of 100 less losses in the resistor, your pull up and series resistor a...

enormous amounts of diagnostics and complex control strategies. Well, we do need complex diagnostics and control as well in order to have anything cool. That's where we need software developers and we need process and testing and... Well, it's depressing how much has to be done to have a useful pro...

One if the advantages of a sensor with a flat response is that you can set a window to 'look' for the valve closing disturbance and then analyse it for disruptive frequencies. It may be worth changing the sensor temporarily to try and see what is going on.

Another choice I made that I wonder about is I used a Schottky diode and also TVS diode on the analog inputs, but maybe the caps and resistors in the filter would have been enough. Those are BAS70XY and a Bussman SURGX respectively. You don't need a TVS, you only need a series resistor followed by ...

Andorra is the 5642/44 and the Mamba is the 5674, I don't think I've ever seen an Intel device in a Powertrain ECU. early Rover MEMS ECUs, made by Motorola, were using Intel CPUs, if that counts that counts :-) I just looked that up, the MGF used an Automotive qualified 87C processor. They don't se...

You don't need a big processor for this king of project, modern ECUs have enormous amounts of diagnostics and complex control strategies. Most of the ECUs that are being replaced here are quite simple devices and manage to handle diagnostics, control and back-up strategies with plenty of processing ...

Andorra is the 5642/44 and the Mamba is the 5674, I don't think I've ever seen an Intel device in a Powertrain ECU.

russian wrote:First draft by @ available at https://svn.code.sf.net/p/rusefi/code/trunk/hardware/ion_sense/

I would highly recommend the use of an automotive quality regulator, the LM7805 isn't suitable for use in an automobile, except maybe as a post regulator.

I was going through some papers yesterday and found another patent application. I looked it up:

http://www.google.com/patents/US20110210745

I'm going to talk to a Harley dealer and see what I can find out about their coils, most companies were closed over the Christmas period.

Everything has a resonant frequency, the weight of the wiring or the wiring moving around or vibrating can cause the response of the sensor to change which can lead to a non-linear response and amplification of unwanted frequencies. If the wiring follows the original factory wiring then it should be...

I'll be watching this with interest, I have designed OEM ECUs using both the Andorra and Mamba, however my software experience is very limited.

What window are you using? you will need to adjust that to suit your engine. How is the knock sensor mounted? it is very important that the mounting surfaces are flat and the sensor is correctly torqued. In a previous job I used to design this type of sensor and interface circuitry, most of the issu...

I thought that you meant that you had a separate input to the ECU from the ignition switch to wake it up and turn on the main relay. It doesn't matter it will work as it is if I include the extra circuitry.

I need an ignition switch input as well, the Mazda ECU doesn't have that either.

It looks like they separate the ignition signals from the others on the connector, I assume they also keep the wiring separate; that wouldn't be easy to do with the Mazda connector. Its easy for Bosch to do they have a lot of R&D money and can make most stuff in house to keep costs down.

russian wrote:It's not enabled and it's flexible. Your config https://svn.code.sf.net/p/rusefi/code/trunk/firmware/config/engines/suzuki_vitara.cpp is now using PE6

Sorry, I meant which pin on the main connector; I may as well keep it the same.

The schematics for my ECU are here:
http://www.rhinoman.org/rusefi/70E10_schematic_ECU.pdf

I won't be implementing the immobiliser functions.