Connector considerations

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oughtsix
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Re: Connector considerations

Post by oughtsix »

Thank you for the welcome!

Sorry if I offended anyone with my comment about MSIII. I have been watching the threads on the MSIII board for quite a while and haven't been able to find much progress. When the MSIII forum started I purposed this stacking / separate connector board idea and was very quickly foo-foo'ed by the designers. I do understand that first versions will be bread boards or such. I really like the idea of a connector board sandwich and was hoping to put the idea in peoples minds. I also COMPLETELY (by this I mean COMPLETELY) agree that soldering DB37's with heavy gauge wires suck and having tried to crimp one with good quality amphenol pins and crimper found this was also futile.

When I said amphenol connector in my above post I used this as a synonym for a good high quality industrial connector that is easy to work with, rugged and weather proof. I have no manufacturer preference.

I really like the idea of a multi connector board with a DB37 and cut off what you don't want. I also really like the idea of having terminal strip connections as an option.

With a "High quality industrial connector" I like the idea of being able to have the main power relay, fuel pump relay and fuses on the connector board. My thought was not to preclude these from being implemented on a separate relay board also. Hmmm.... could the relay portion of the connector board be on the 4th side of the board sans Ford OEM connector and also be able to cut it off AND deploy it standalone????
Last edited by oughtsix on Tue Mar 24, 2009 7:11 am, edited 1 time in total.
oughtsix
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Re: Connector considerations

Post by oughtsix »

Is it OK / Legal to post an image link to the MSIII external wiring diagram or do I need to kill this post?
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Fred
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Re: Connector considerations

Post by Fred »

oughtsix wrote:Is it OK / Legal to post an image link to the MSIII external wiring diagram or do I need to kill this post?
Image
Fine by me, but your images won't work. MS block links to them from us by referrer. You need to use a proxy like this and just post a link :

http://anonym.to/?http://www.megamanual ... wiring.gif

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AbeFM
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Re: Connector considerations

Post by AbeFM »

Uh oh, I sense an outvoting here.

Let me just touch again on what I'm getting at (and I think fred's comments there are the most relevant)

BETA BETA BETA BETA BETA!

Heh. The idea is to get something up ASAP which people can test, the "shoebox" you're talking about, or shoehorned? Anyway... I'm not talking about the second generation of these, which I agree, should have car specific connectors - I have NO problem drawing these up (hell, I already have one for my car half done). When I think testing, I think... I may very well plug this in, crank the motor once, find 6 problems, and be hacking on it. Do I really want to design a custom board for this?? No. I want to have 4 other people who also expect this to *maybe* work at all to have something quasi-standard, and be able to get the parts, and work out the bugs.

When the first boards that have run a car have been done, it makes sense to come up with some of these other quite clever and very valuable ideas. I just don't think it's a good place to start - if a pin moves on the stacked connector, what are you going to do with 25 BMW 325i series boards which are all wrong? Blue wire each one?

Two more points, then I'll stop ranting. :-)

1) I probably should have said Alpha, not beta. We can make a nice set up using something very standard like a set of DB's, and despite all the complaining, I've seen them used in many high-rel situations without failure. My own car (everyone who runs an MS) runs these and they don't have problems!!!!
1b) Whoever writes the code for a wheel will likely be the one with the motivation to do the connector board for a specific car. One board with all the connectors is impratical, but you might be able to gang up two or three + a jimstim connector per board if people work together.

2) stock wire gauge is typically pretty small. Especially for a short test, are you really that worried? My DB37 has adjactent pins jumped and wires coming off of that. Gives me the current capacity I need. Again, not IDEAL, but perfect for a quick test.


I guess I'm just saying I think it's a mistake to believe you're going to spin one board and have every car work perfectly with it. Or, any car. Count on a respin, do the first quick and dirty, and get it in cars ASAP. Then you'll know what you need to know to do the second one. And yes, anyone who buys in on the very first spin of the board is doing it knowing the design of at least the connector board will change.

One last suggestion: Why not a standard stacking connector on the bottom for a connector board, one with the higher currents, etc, but not the same bus as the CPU? Or did someone already say this and I missed it?
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Fred
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Re: Connector considerations

Post by Fred »

Great post Abe, I'm with you there. I think at least some of the board efforts are in preparation, ie, make sure that when we need something standardised it is close to available. At the end of the day this is 100% flexible hardware wise, no pressure to use xyz from manufacturer abc.

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jharvey
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Re: Connector considerations

Post by jharvey »

The stack connector is fairly low current. The back plane (or should I say center plane) is data only. The wires from the injectors and such aren't part of that connector, and can easily have much larger wires attached, that run down to the connector card.

I don't think we really need to standardize on a connector. Perhaps a template connector card would be handy, something with a Jim stim on one side, and a field usable connector on the other. Once the first one exists, then anyone can copy it and make their own version. I might even wager, that the first one is Jim stim only. However, who ever makes the first, leave room for an other at the end ;)
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AbeFM
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Re: Connector considerations

Post by AbeFM »

I agree. Just having the jimstim connector on one side will likely be most of the standardization needed. Certainly on the other side, for the same cost, I'd have a footprint for two connectors, maybe a male and a female 25 pin or something. Whatever. :-)
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jharvey
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Re: Connector considerations

Post by jharvey »

Do I recall your connector card was for a MS unit? I'm curious have you posted that file somewhere? If so that might make a nice starting point for someone who wants to make a connector card.
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Re: Connector considerations

Post by AbeFM »

jharvey wrote:The stack connector is fairly low current. The back plane (or should I say center plane) is data only. The wires from the injectors and such aren't part of that connector, and can easily have much larger wires attached, that run down to the connector card.

I don't think we really need to standardize on a connector. Perhaps a template connector card would be handy, something with a Jim stim on one side, and a field usable connector on the other. Once the first one exists, then anyone can copy it and make their own version. I might even wager, that the first one is Jim stim only. However, who ever makes the first, leave room for an other at the end ;)
Oh, man, talk about awesome - if you set up jumpers right, you could have it so that any input could come from the car OR the jimstim, at the same time. I've done this before, for instance, to fake cam/crank signals while letter the car's fans run, etc.

Do I recall your connector card was for a MS unit? I'm curious have you posted that file somewhere? If so that might make a nice starting point for someone who wants to make a connector card.
Yeah - it is, it's MS on one side, 99-00 Miata (but somewhat configurable) on the other. At minimum the connector (which I could share the footprint for) is used on Miatas and Civics. It's available to anyone who wants it, though I would rather not out-and-out post the drawings.
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