[Diy_efi] Microcontroller based Auto Related Projects

Thu Nov 15 23:26:18 UTC 2012

I'd been doing some reading and searching. Came across a website that
mentions "manifold pressure value is multiplied by the rpm value to
determine the primary pulse width (of injector).

1. Can someone please elaborate on this. I know what MP and rpm are but how
exactly is this done?

2. Is this a good method and/or are there any other methods available?

Thanks.
On Nov 6, 2012 12:18 PM, "Fred Cooke" <fred.cooke at gmail.com> wrote:

> FreeEMS is no hobby, it's serious business ;-)
>
> On Tue, Nov 6, 2012 at 1:11 AM, xyz Q <xyzqhtc at gmail.com> wrote:
>
>> Thanks for the links. Regarding the part I only asked because it seemed
>> expensive for diy/hobby. Regardless, it's a good one.
>>
>>
>> On Tue, Nov 6, 2012 at 1:15 AM, Fred Cooke <fred.cooke at gmail.com> wrote:
>>
>>> Yes, that's me! Fiji, eh, interesting! :-)  The FreeEMS project will
>>> always have a strong Kiwi feel to it, but it's truly a global affair now,
>>> with dev occurring or occurred in at least 8 countries so far, and 14+ very
>>> different vehicles running/run in 5 countries.
>>>
>>> Another thing you could play with at the lower end of the scale is
>>> SECU-3, a Russian project with maybe 50 users and a lead dev that
>>> speaks/writes English reasonably well (rare there it seems). Links for that:
>>>
>>> http://forum.diyefi.org/viewforum.php?f=47 forum section
>>> http://forum.diyefi.org/viewforum.php?f=51 English section
>>> http://secu-3.org/?lang=en New site without any English content, old
>>> one was fairly complete...
>>>
>>> I don't have time to explain MCU choice in detail, but the decision was
>>> made nearly 5 years ago, before MS3 was publicly mentioned for the first
>>> time, and came down to dev tool availability, peripherals, pin count, power
>>> and temperature ratings, among other things. Other choices that appear
>>> attractive aren't as good as they seem in many cases, even 5 years on.
>>>
>>> Fred.
>>>
>>> On Mon, Nov 5, 2012 at 4:11 AM, xyz Q <xyzqhtc at gmail.com> wrote:
>>>
>>>> Hi, thanks for the link not that I might be able understand much of it.
>>>> Should have never left SW back in tech school. I'm a RF guy (mobile comms)
>>>> by the way. I was reading through some sites and came across a "Fred Cooke"
>>>> at diyefi.org, so I'm assuming its you. Its so great to see a good
>>>> quality, thorough project NZ. I live in Fiji b.t.w. Can you say why you
>>>> chose the freescale part?
>>>>
>>>> Thanks and regards.
>>>> Nikhil
>>>>
>>>> On Fri, Nov 2, 2012 at 12:30 PM, Fred Cooke <fred.cooke at gmail.com>wrote:
>>>>
>>>>> Something simple to get started on, that Delco reminded me of, is
>>>>> Jason Roughley's PIS software, check it out here:
>>>>>
>>>>> https://github.com/Torture/PIS
>>>>>
>>>>> It's very basic and PW driven, but PW is his thing, he's not a VE fan
>>>>> :-)
>>>>>
>>>>> Regards,
>>>>>
>>>>> Fred.
>>>>>
>>>>> On Thu, Nov 1, 2012 at 11:47 PM, Bill Shaw <b.shaw at comcast.net> wrote:
>>>>> > Yes,  there's lots of info out there.  You will find more interesting
>>>>> > reading at http://www.sae.org/.
>>>>> >
>>>>> > Slight subject change - I brought home a new(er) dd yesterday,  a
>>>>> 2010
>>>>> > Camaro SS.  Sweet ride,  bad news is it's got a Bosch ecu!
>>>>> >
>>>>> > Thanks for the e-book link.
>>>>> >
>>>>> > Bill
>>>>> >
>>>>> >
>>>>> > On 11/1/2012 6:03 PM, xyz Q wrote:
>>>>> >
>>>>> > Driving a vehicle that would have your own designed and built ecu
>>>>> could feel
>>>>> > like a 'mystical' experience, some what.
>>>>> >
>>>>> > We still run right, considering it was a major source of
>>>>> transportation a
>>>>> > 100+ years ago now its mostly for recreational.
>>>>> >
>>>>> > I just think there's so little info pertaining to ecu controls even
>>>>> basic
>>>>> > ones that probably its worth looking into.
>>>>> >
>>>>> > On Nov 2, 2012 8:40 AM, "David Allen" <davida1 at hiwaay.net> wrote:
>>>>> >>
>>>>> >> I always like microcontroller projects, have built some interesting
>>>>> >> things, too. I was considering trying to build an ECU, but then I
>>>>> realized
>>>>> >> something.  For me; with my project goals, GM had already
>>>>> engineered the
>>>>> >> perfect ECU. It's so good that millions of them are out there on
>>>>> the road
>>>>> >> today. Every parameter is configurable and the hardware is
>>>>> bulletproof. So I
>>>>> >> went with a Delco 1227730 ECU, and focused my microcontroller
>>>>> projects on
>>>>> >> other areas.  I made projects for where there aren't off-the-shelf,
>>>>> highly
>>>>> >> cost-effective solutions already available.  I've built auto
>>>>> headlights
>>>>> >> controller, air-levelling suspension controllers, parts-washer
>>>>> controller,
>>>>> >> heat pump controller, speedometer calibration modules, and other
>>>>> odds and
>>>>> >> ends. But the Delco ECU is just too cheap, available, rugged, and
>>>>> just plain
>>>>> >> good at what it does to re-invent the wheel for an engine ECU. The
>>>>> learning
>>>>> >> curve was a little steep learning the tuning, because there is SO
>>>>> MUCH in
>>>>> >> the ECM program. But it was worth it in the end, because it's so
>>>>> >> configurable.
>>>>> >>
>>>>> >> This is just my OPINION and I hope you guys take it as that. Not
>>>>> meaning
>>>>> >> to discourage anyone. I wanted to tell about the end result of when
>>>>> I went
>>>>> >> down the same path and the final decision I came to.
>>>>> >>
>>>>> >> Respectfully,
>>>>> >> David
>>>>> >>
>>>>> >> ----- Original Message -----
>>>>> >> From: xyz Q
>>>>> >> To: diy_efi at diy-efi.org
>>>>> >> Sent: Thursday, November 01, 2012 3:26 PM
>>>>> >> Subject: Re: [Diy_efi] Microcontroller based Auto Related Projects
>>>>> >>
>>>>> >> All this is ok. But I'm thinking in order to get started, wouldn't
>>>>> be be
>>>>> >> good if some experts could hold some basic ruts on this forum.
>>>>> Let's see
>>>>> >> what some have to say, mainly very specific info eg., rpm counting,
>>>>> etc,
>>>>> >> etc... But I know time would be a big issue for many.
>>>>> >>
>>>>> >> I downloaded some notes from Freescale on 68HC08 to introduce me to
>>>>> >> Motorola MCUs. My only experience is with 80x86 MPU from back in
>>>>> tech
>>>>> >> school.
>>>>> >>
>>>>> >> Anyways, here's an offtopic link that some might find useful. It's
>>>>> got
>>>>> >> premium ebooks on just about every subject for free.
>>>>> >>
>>>>> >> www.freebookspot.es
>>>>> >>
>>>>> >> On Nov 1, 2012 1:06 PM, "Alan To" <toalan at 14point7.com> wrote:
>>>>> >>>
>>>>> >>> For me 5v operation is a must have so to be able to work with the
>>>>> widest
>>>>> >>> range of sensors possible without additional burden of resistor
>>>>> dividers.
>>>>> >>> The MPC555x is a $30 uC, you are doing some high end stuff, for
>>>>> high end
>>>>> >>> stuff priorities are different, if you need to work with 5v
>>>>> sensors the cost
>>>>> >>> of 0.1% or better tolerance resistors or an external ADC is
>>>>> probably not an
>>>>> >>> issue. Originally we were talking about uCs in the same league as
>>>>> the 8 bit
>>>>> >>> PICs, AVRs, and perhaps as high as ARM Cortex M3/M4.
>>>>> >>>
>>>>> >>> Regards
>>>>> >>>
>>>>> >>> Alan To
>>>>> >>>
>>>>> >>>
>>>>> >>> On 10/31/2012 5:41 AM, Bill Shaw wrote:
>>>>> >>>
>>>>> >>> The operating voltage is not a significant decision factor when
>>>>> choosing
>>>>> >>> an automotive microprocessor.  The MPC5554 we are using has a 1.3
>>>>> volt core
>>>>> >>> and 3.3 volt I/O.  It is an awesome  automotive microprocessor,
>>>>>  but the
>>>>> >>> array of peripherals and registers would be a bit daunting for the
>>>>> >>> uninitiated.
>>>>> >>>
>>>>> >>> Best,
>>>>> >>>
>>>>> >>> Bill
>>>>> >>>
>>>>> >>> On 10/31/2012 12:16 AM, Alan To wrote:
>>>>> >>>
>>>>> >>> It is a 3.3v chip and you really want 5v operation for automotive.
>>>>> The
>>>>> >>> new Arduino Due will be a trainwreck, an epic one.
>>>>> >>>
>>>>> >>> On 10/30/2012 6:47 PM, xyz Q wrote:
>>>>> >>>
>>>>> >>> There's an ARM based Arduino. What would you say about that for a
>>>>> choice?
>>>>> >>>
>>>>> >>> On Oct 31, 2012 1:22 PM, "Avery Nisbet" <anisbet at gmail.com> wrote:
>>>>> >>>>
>>>>> >>>> 1.  Most of the hack a day projects are by IT/computer sci guys
>>>>> that
>>>>> >>>> look down on getting their hands dirty with cars. If you look
>>>>> deeply
>>>>> >>>> at some of the projects they will have really shoty electrical
>>>>> >>>> engineering in them. Some of them are pure hacks and would not
>>>>> work in
>>>>> >>>> a production sense.  Some are pretty decent.
>>>>> >>>>
>>>>> >>>> 2. Pics from an architecture point of view kinda suck. They were
>>>>> not
>>>>> >>>> designed for use with stack based compilers(One working register).
>>>>> >>>> The Motorola stuff was some of the 1st used in the automotive
>>>>> space.
>>>>> >>>> The architecture lends itself to use with a compiler.  They are
>>>>> >>>> designed for the harsher automotive environment.  Some will say
>>>>> they
>>>>> >>>> have nicer hardware peripherals.  I would say some of the
>>>>> peripherals
>>>>> >>>> were designed specifically for the automotive market. There is
>>>>> also a
>>>>> >>>> pretty big code base to look at.  Oh and mostly anyone who went to
>>>>> >>>> school for software or hardware who is older than say 30 was
>>>>> forced to
>>>>> >>>> learn 6800(68HC11) or 68000 assembly language.  This usually
>>>>> involved
>>>>> >>>> getting ahold of the purple data books motorola gave away for free
>>>>> >>>> that were well enough written so you could get your class work or
>>>>> real
>>>>> >>>> work done. I probably have 2 or 3 copies of the 68HC11 books
>>>>> laying
>>>>> >>>> around somewhere. This being said there are many other options
>>>>> today
>>>>> >>>> and I would look to ARM or AVR before I looked at PIC.  ARM is
>>>>> already
>>>>> >>>> dominating the cheap 32bit market and is pretty easy to pick up.
>>>>> This
>>>>> >>>> will help in the job search later. AVR's are pretty good for the
>>>>> 8bit
>>>>> >>>> scene.  GCC supports them and ATMEL makes some automotive
>>>>> environment
>>>>> >>>> parts.
>>>>> >>>>
>>>>> >>>> 3.  Go get yourself an Arduino(or other uC of choice), BIP373(OR
>>>>> GM
>>>>> >>>> ignition module) and some optoisolators.  Then build a distributor
>>>>> >>>> and/or crank trigger based ignition system. Then try turning that
>>>>> into
>>>>> >>>> a full engine management solution using the peak and hold add in
>>>>> board
>>>>> >>>> by Jbperf. Start researching the mega squirt schematics at the
>>>>> timing
>>>>> >>>> input(tach) and the ignition output. Build those circuite on a
>>>>> bread
>>>>> >>>> board and test on a bench. Then move them on to your test engine.
>>>>> It
>>>>> >>>> could be a lawn mower engine or a V8 monster. Read up on timing
>>>>> >>>> advance and program the Arduino to do a simple RPM only based
>>>>> timing
>>>>> >>>> curve.  Then add a MAP and/or TPS sensors and add load as a
>>>>> factor of
>>>>> >>>> your timing curve.  Then engine temp to add some cold start
>>>>> advantages
>>>>> >>>> and you have all the sensors needed to do open loop EFI.  After
>>>>> adding
>>>>> >>>> injectors you could add a wide band O2 sensor such as the LC-1
>>>>> from
>>>>> >>>> innovative motor sports or just a heated narrow band for cruze.
>>>>> >>>>
>>>>> >>>>
>>>>> >>>> -Avery
>>>>> >>>>
>>>>> >>>>
>>>>> >>>> On Mon, Oct 29, 2012 at 8:13 PM, xyz Q <xyzqhtc at gmail.com> wrote:
>>>>> >>>> > Hi, I've been on the list for some time, on and off mainly
>>>>> reading
>>>>> >>>> > bits,
>>>>> >>>> > trying to find some interesting ideas. Unfortunately I was 10
>>>>> years
>>>>> >>>> > too
>>>>> >>>> > late, when this forum had been in its prime.
>>>>> >>>> >
>>>>> >>>> > So here are my first set of questions that I hope on getting
>>>>> some
>>>>> >>>> > answers,
>>>>> >>>> > hopefully.
>>>>> >>>> >
>>>>> >>>> > 1. Why are there so little auto related uc based projects and
>>>>> ideas
>>>>> >>>> > out
>>>>> >>>> > there on the net? Look at hackaday.com, for example. Many
>>>>> projects,
>>>>> >>>> > talented
>>>>> >>>> > people but all they do is prove a point that some thing can be
>>>>> done.
>>>>> >>>> > But
>>>>> >>>> > guess what hardly something is really useful. I may have missed
>>>>> some
>>>>> >>>> > good
>>>>> >>>> > worth while so please put them here if you know.
>>>>> >>>> >
>>>>> >>>> > 2. If PICs are so popular, why are Motorola MCUs popular with
>>>>> auto
>>>>> >>>> > projects?
>>>>> >>>> > In terms of features aren't they on the same "level"?
>>>>> >>>> >
>>>>> >>>> > 3. The way I see to learn microcontroller based EMS or ignition
>>>>> is to
>>>>> >>>> > look
>>>>> >>>> > at it piece by piece. Megasquirt is great but it's hard to
>>>>> learn a
>>>>> >>>> > complete
>>>>> >>>> > system. Aren't there any web sites (I've seen DIYEFI) that have
>>>>> info
>>>>> >>>> > on say
>>>>> >>>> > ignition control, RPM handling with an MCU or other basic
>>>>> control
>>>>> >>>> > concepts
>>>>> >>>> > that can form the basis for EMS/Ign. related projects. I'd like
>>>>> to
>>>>> >>>> > learn the
>>>>> >>>> > basics and if there are specific approaches to this, I'd like
>>>>> to hear
>>>>> >>>> > your
>>>>> >>>> > side of the story. It would be helpful.
>>>>> >>>> >
>>>>> >>>> > Thanks and regards to all on the forum. Some projects here are
>>>>> really
>>>>> >>>> > nice
>>>>> >>>> > and inspiring.
>>>>> >>>> >
>>>>> >>>> > Nik.
>>>>> >>>> >
>>>>> >>>> > _______________________________________________
>>>>> >>>> > Diy_efi mailing list
>>>>> >>>> > Diy_efi at diy-efi.org
>>>>> >>>> > http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>>> >
>>>>> >>>> _______________________________________________
>>>>> >>>> Diy_efi mailing list
>>>>> >>>> Diy_efi at diy-efi.org
>>>>> >>>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>> _______________________________________________
>>>>> >>> Diy_efi mailing list
>>>>> >>> Diy_efi at diy-efi.org
>>>>> >>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>> _______________________________________________
>>>>> >>> Diy_efi mailing list
>>>>> >>> Diy_efi at diy-efi.org
>>>>> >>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>> _______________________________________________
>>>>> >>> Diy_efi mailing list
>>>>> >>> Diy_efi at diy-efi.org
>>>>> >>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>>
>>>>> >>>
>>>>> >>>
>>>>> >>> _______________________________________________
>>>>> >>> Diy_efi mailing list
>>>>> >>> Diy_efi at diy-efi.org
>>>>> >>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>>
>>>>> >> ________________________________
>>>>> >> _______________________________________________
>>>>> >> Diy_efi mailing list
>>>>> >> Diy_efi at diy-efi.org
>>>>> >> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>
>>>>> >>
>>>>> >> _______________________________________________
>>>>> >> Diy_efi mailing list
>>>>> >> Diy_efi at diy-efi.org
>>>>> >> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >>
>>>>> >
>>>>> >
>>>>> > _______________________________________________
>>>>> > Diy_efi mailing list
>>>>> > Diy_efi at diy-efi.org
>>>>> > http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >
>>>>> >
>>>>> >
>>>>> > _______________________________________________
>>>>> > Diy_efi mailing list
>>>>> > Diy_efi at diy-efi.org
>>>>> > http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>> >
>>>>> _______________________________________________
>>>>> Diy_efi mailing list
>>>>> Diy_efi at diy-efi.org
>>>>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Diy_efi mailing list
>>>> Diy_efi at diy-efi.org
>>>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>>
>>>>
>>>
>>> _______________________________________________
>>> Diy_efi mailing list
>>> Diy_efi at diy-efi.org
>>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>>
>>>
>>
>> _______________________________________________
>> Diy_efi mailing list
>> Diy_efi at diy-efi.org
>> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>>
>>
>
> _______________________________________________
> Diy_efi mailing list
> Diy_efi at diy-efi.org
> http://lists.diy-efi.org/mailman/listinfo/diy_efi
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.diy-efi.org/pipermail/diy_efi/attachments/20121116/8baab0ea/attachment-0001.html 