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Technical Megasquirt

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Technical Megasquirt

Apart from SPR1-4 all the top row pins are earths. I only need a few earth to chasis, so the rest, once remove and done like that, are fair game.

I can now run fully seq inj and ign, plus 2 speed inputs, fan, tacho, and a few other bits from the one connector :)

Kristian
 
Well, The MS itself doesn't draw much current, only the injectors, stepper and coils really.

My coil drivers are off board, so I only have injectors and IAC. Even with the mods I still have 4 GND free, and also 4 pins for any future expansion.

each pin is capable of 6.5 - 7 Amp's so 28Amps. Still more than enough for a whole host of coil drivers if kept on board :)

Capture.PNG

On another note, anyone played with barometric compensation? I have two spare mpx4250 lying about now :D
 
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I'm also looking at removing the serial chip from the PCB and replacing it with USB.

I have had great success with FTDI products and drivers, so am looking at:

TTL-232RG-VSW5V-WE
or
TTL-232R-5V-PCB

by http://www.ftdichip.com/

You can buy direct or other retailers as well.

It'll allow you to plug a USB straight in and communicate with the MS :) That's the plan anyway :slayer:

Just deciding which one to go with now.

//edit -- gone for this one: TTL-232R-5V-AJ . Got it from rswww.com as it's cheaper and I can collect :)

ftdichip.jpg

I'll panel mount a 3.5mm audio jack the same end as the DB37, and have everything out the one end.

I'll report how/if it works once it arrives :)
 
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Nope, the MS processor outputs standard TTL output. The chip on the PCB then converts this to RS232....most people then get a USB serial to RS232 convertor, or are lucky enough to have RS232 serial on the laptop.

Doing it this way, the USB sets up a virtual serial com port on the computer, this cable interfaces direct with 5V TTL signals, so you can go straight from USB to processor.

Should make things more elegant and technically reliable, as there are less steps involved :)

I get the cable tomorrow morning, so hopefully I can test in the afternoon :)
 
Well thats MS back on track. Idling pretty nicely. Just need to tidy up all the engine bay wiring and take it for a drive with autotune. The main problem was that the timing was way out. The guy found it strange that he couldnt use trigger wizard and had to change via angle(deg BTDC). Has done the job fine though. The idle stepper is set up and working now too. So if you know what you are doing its a good system. Took him all of a couple hours to get it to this stage. :worship: Was quite impressed with the standard of the work so far, which is a bonus.

Will get a MAP and datalog up hopefully this evening if it doesnt rain.
 
I wonder how many times in the thread I've said "check to timing", not only to yourself but others lol. It's pretty vital for everything else to work :D

Glad it's back on track though! :slayer:


Looks like my old msq's have a BTDC of 94 degrees. I'll know for sure if thats right in a week or two when it lives again :D
 
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MS2 V3 with the 3.1.0 firmware with the additional Mario_b mods, the latest idle code fixes to give higher idle resolution and a few other mods. Including Sequential Injection and VICS Control

All fitted by my own fair hand (well Jason gave me a hand swapping the old lambda sensor out)

But took the easy option and got someone to build it for me with a PNP harness cost me a whole £360 for the built MS plus £125 for AEM wideband and £40 for full version of tuner studio MS, now busy tuning and burning out what is left of my clutch
 
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