40pin DIP to processor daughter board idea

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soapypanther
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40pin DIP to processor daughter board idea

Post by soapypanther »

I'm not sure if this has come up in the past, but I would like to proceed with this plan if this is feasible.

I am currently running Megasquirt 2 but on a main board of my own design. Like many of you, I found several shortcomings to the standard board and wished to improve on the original. As my setup currently sits, it shares almost nothing with the standard v3.0 board that I started with.

I am using most of the overly-stout large components from a Siemens MS41.1 ecu. The power supply, FET arrays for all high current outputs and the ignition drivers have been reused and I now use the MAX9926 chip for engine position sensors. The only circuit still similar to the original is the temperature and TPS sensor input section. It works very well and has been very reliable.

I would like to retain my known working main board and use a daughter card with your ECU to feel the waters and get it running. Hopefully, I can provide a useful test bed for code development. I am especially interested in stable idle control and a few other stock ecu functions MS cant do (well.) So this would resemble the Megasquirt 3 daughter card; a larger CPU pinned out to the DIP40.

Am I on the right path? Any recommendations?

I am interested in a pin assignment chart (is there a permanent one?) for the CPU. Any help is greatly appreciated.
Last edited by soapypanther on Thu Feb 14, 2013 8:59 am, edited 1 time in total.
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Fred
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Re: 40pin DIP to processor daughter board idea

Post by Fred »

Welcome! :-)
soapypanther wrote:I'm not sure if this has come up in the past, but I would like to precede with this plan if this is feasible.
It has, hopefully someone else (please!) will give you the link to the thread. Additionally, someone contacted me recently about doing the same and I spoke to him on skype. I'll link him to this thread too.
I am currently running Megasquirt 2 but on a main board of my own design.
Tsk tsk, I won't tell! :-) You can share pictures of it in non-free (I'm always curious), but don't share the design here, please. Not yet, anyway.
Am I on the right path? Any recommendations?
That's kinda up to you. It's something that I thought of long ago, as have many others. In the end I deemed it too much hassle for not enough gain. If you want to, though, go right ahead. Perhaps team up with the other guy to prevent wasted effort?
I am interested in a pin assignment chart (is there a permanent one?) for the CPU.
There isn't a permanent one, and won't be for a while. Three sources of info on this. Issue 190. RavAGE schematics. And outdated/old spreadsheet in firmware repo.

I'll de-n00b you now so you can find all of those easily.

Fred.
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soapypanther
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Re: 40pin DIP to processor daughter board idea

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Haha, is it not "legal" to run an MS2 daughter card on a custom PCB? I suppose I can't call it "Megasquirt" legally anymore. I have enough v3.0 boards laying around, I think I have payed my licencing dues many times over... and still had to make my own.

Anyways, I would love to collaborate to split the cost, time, and headach. I am torn between having a custom daughter card printed or just wiring in the dev board. Both cost about the same. I would ultimately like to have a new mainboard printed with the ECU integrated, but as I understand it, 6 cyl sequential is not possible yet? Also, this is on a 60-2 crank setup. I have read this is not supported, but the info I have run across is a little dated. Ill keep reading...
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Dan
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Re: 40pin DIP to processor daughter board idea

Post by Dan »

a simple 40pin dip would be simple as to do. After I sort out the RavAGE stuff I have on my agenda, I would be more than happy to assist with this :-)

either that or you can wait a little while and you could grab a RavAGE unit? :-)
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Fred
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Re: 40pin DIP to processor daughter board idea

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Sounds like he's capable of designing it himself? That other guy I mentioned said that he'll post some comments here soon, so sit tight for that.

Re "legal" doing it is not illegal, even in the US, but sharing the work is, only in the US. You're in the US. So is this server, though that may change.

6 sequential is possible, but only with fuel only or ignition only, otherwise both must be semi seq/wasted spark.

60-2 works, and has run one engine, but performance is BAD. I'll fix it pretty soon, as it's holding back the owner of that car.

Fred.
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Dan
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Re: 40pin DIP to processor daughter board idea

Post by Dan »

ah sweet then! no worries at all!

If you need anything please feel free to ask! :-)
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Re: 40pin DIP to processor daughter board idea

Post by Dan »

RavAGE RC2 schematics are located here --> https://github.com/dvisser/Ravage/blob/ ... f?raw=true

Page 1 should give you an idea as to what CPU pins are "critical" ones.

Hope that helps a little!

:-)
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Re: 40pin DIP to processor daughter board idea

Post by Arttu »

Hi all.

I'm the person who Fred mentioned. My current plan is to make a processor board that is electrically compatible with MS3 board. The first goal is to see if I can use the FreeEMS on my bike that is currently equipped with MS3 processor and "alternative" main board ;) If it works out well this could be an interesting solution for anyone who is willing to try the FreeEMS and has ready MS installation.

At the moment I'm just on initial stages with the project. I have been studying Ravage and other schematics and everything looks feasible and quite straightforward to me. The design task shouldn't be extremely huge but unfortunately I have quite limited time available for this at the moment. My current estimation is that I may have first prototype ready around May-June.

Some kind co-operation sound good for me too :)
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Re: 40pin DIP to processor daughter board idea

Post by soapypanther »

Dan, thank you for pointing me to the schematics! Very thourogh and CPU protective? I noticed the ignition drivers are very isolated from the CPU signal. I currently have mine driven straight from the CPU with a pull down resistor and inline resistor. Is there any reason this would not be safe with the new CPU? Otherwise, it appears everything else is very simmilar to what I have already done with mine.

Arttu, I would love to get a collaboration going. I am running MS3 on my DD and would love to start with that one. I was thinking I could keep the pinout the same on both the DIP and the headers. Thoughts? Maybe even the dimensions could be kept the same. This way, I can swap back and forth on the fly.

I am a little busy at the moment as well, I just started medical school and the work is piling up. This is just my hobby though, and I find fiddling with my car theraputic. Im going to start drafting a daughter card this weekend I hope. What priorities do you have for the card Arttu? I would like to include serial communication chip, a MAX chip for VR conditioning, the crystal and assiciated clock circuitry. Anything else you think I should add? I think I could have a couple done for less than $100 each I hope.

What are your vehicle specs? Im running a BMW straght 6, COP wasted spark and batch fire high Z injectors. I have a VR sensor on a 60-2 wheel at the crank and a funny proximity sensor on the cam not currently used (hopefully soon to change). I may use a schmitt trigger to simulate a hall signal or take care of this in the code perhaps.

Fred, with the pin assignment, can I use six ports for injectors and six for ignition and run wasted/semisequential through the code or do I need to tie the high current drivers in pairs?

Thank you all again. Hopefully, soon I can contribute. Is there anything I can do to hurry along the 60-2 support.
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Re: 40pin DIP to processor daughter board idea

Post by Fred »

Your CPU drives your external ignitors directly? Typical M$ hack job, then? :-) They're not isolated so much as featured. At the least you need a current buffer/amp. However MUCH better is to use a higher voltage output for external ignitors. There is no, and will likely never be any, software invert on the outputs - this is just plain broken as a concept. The first "stage" is for that, which you can omit, if you don't need it for SAAB CDI or similar weird stuff.

Look at the injector page of the schematic for recommended wiring for the time being. IE, tie it in hardware. You can configure down in channels, but there are 6 max, and you can't configure up.
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