FREEEMS hardware schematic and PCB

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gearhead
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Re: FREEEMS hardware schematic and PCB

Post by gearhead »

I need to chime in here, too. I was looking at stuff a while back and it just sounded easier to me to build a DB37 swappable system on a single board (no TA card). This will allow the number of us developers to swap in a complete system on our systems that currently run MS.

I posted this somewhere and lost steam as work picked up this summer.

Basically: 4 layers, use the chip layout portion shown in the Freescale docs, put the chip on the board, put a Power supply, serial chip, BDM header, basic AD input circuits (MAP, IAT, CLT, TP, O2, Bat), 2 optos for cam and crank, 6 low power ign outputs, 6 Hi Power inj outputs (with buffers), 6 low power circuits that can be jumpered as I or O and have a DB37 for the I/O connector but a audio plug for serial as it is simpler and we don't need 9 stimking pins... This way it can be easily swapped out for development purposes. On mine, anyway, I have a 4 pin external plug for ign output (2n2222s) and a 6 pin external plug for injector output (2 Fet drivers and 4 vnd5n07s)

The rest of the pins need to go to headers. I do not think we can do just one, but at least be able to stack an expansion board on top of this to get to all the pins.

I think this can all be fit on the same size board as used for MS so that we could re-use the case, even.

Thoughts?

Gearhead
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Fred
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Re: FREEEMS hardware schematic and PCB

Post by Fred »

My only thought on that is that you'll need to use a T/Y/breakout setup to let MS continue to handle whatever we currently don't at any point in time. Right now the biggy is no ign, but also fuel pump and idle air could be a concern.

Fred.
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sry_not4sale
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Re: FREEEMS hardware schematic and PCB

Post by sry_not4sale »

Just wire your fuel pump up to your park lights - worked for me :lol:
Owner / Builder: 1983 Mazda Cosmo 12at (1200cc 2-rotor turbo) coupe [SPASTK]
165hp @ 6psi standard - fastest production car in japan Oct 82
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Fred
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Re: FREEEMS hardware schematic and PCB

Post by Fred »

Aaron's blood line :

Image

:-p
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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sry_not4sale
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Re: FREEEMS hardware schematic and PCB

Post by sry_not4sale »

(which is not reflected in his Python in any way) :lol:
Owner / Builder: 1983 Mazda Cosmo 12at (1200cc 2-rotor turbo) coupe [SPASTK]
165hp @ 6psi standard - fastest production car in japan Oct 82
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