Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

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Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Ruffcut »

Hi, This is my build thread for my 0.7 Alpha board hopefully not unlucky serial number 13. My board has now arrived thanks DeuceEFI. So I am looking at my BOM order. I did consider doing a really cheap build ala viewtopic.php?f=67&t=2225 as I am already running on MS so I know the wiring inside out. But all the parts that can be missed off are not the expensive ones so I did not think it would be worth it in the long run.

Differences from the Suggested BOM

-For my install I am running 2 banks of 4 injectors resistance on each bank of 4to 5 ohms, so I think a single MOSFET to drive each bank should be fine. Also dropping the resistors and diodes that support the unused MOSFETs .

-Dropping the 0ohm links as they wont be needed.

-The stock bias resistors on the temp sensors are 1800ohms so will be going with them.

-VR sensor so customizing BOM for that.

-Will allways be NA so going with MPXA6115AC6U.

-Ditching the pin headers.

Any suggestions are welcome. Thankyou everyone for great project.

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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Fred »

Ruffcut wrote:Hi, This is my build thread for my 0.7 Alpha board hopefully not unlucky serial number 13. My board has now arrived thanks DeuceEFI.
You think that's bad? Mine showed up without a serial number at all! I'm hoping he'll tell me what they're supposed to be so I can scratch it on myself, otherwise I'm going to scratch PI in there in protest! :-D
So I am looking at my BOM order. I did consider doing a really cheap build ala viewtopic.php?f=67&t=2225 as I am already running on MS so I know the wiring inside out. But all the parts that can be missed off are not the expensive ones so I did not think it would be worth it in the long run.
Wise choice.
-For my install I am running 2 banks of 4 injectors resistance on each bank of 4to 5 ohms, so I think a single MOSFET to drive each bank should be fine. Also dropping the resistors and diodes that support the unused MOSFETs .
Yes, that's fine, except consider keeping a couple for future software updates and/or extra features like dual staged fans or whatever else you dream up.
-Dropping the 0ohm links as they wont be needed.
I strongly recommend that you bridge your grounds optimally. They would be hooked together as a single bus with 8 holes if not for the purpose of being able to separate them into groups with different purposes. IE, for your two injector FETs, at the least, you should join them together and run two redundant wires. If you're really not going to use any FETs, you could bridge in another two and run 4 wires, but this would be mild overkill.
-The stock bias resistors on the temp sensors are 1800ohms so will be going with them.
What are the stock sensors curves like? This rules you out of using library curves. But your sensor may have already done that.

Do you live in a flat place? Or drive up mountains a fair bit? If the former, you could ditch the AAP and save a few bucks. If the latter, we'll have support for AAP algorithms in future.
-Ditching the pin headers.

They're not something I recommend or use, either, FYI.
Any suggestions are welcome. Thankyou everyone for great project.
On behalf of the rest of the team: You're most welcome! :-)

Fred.
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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Ruffcut »

Thanks for your comments Fred.

At some point, if the firmware supports it, I do fancy trying a duel injector arrangement. Seems like a easy mod to the engine to get a few more BHP. I was thinking I would add the MOSFETs at that point, but I do want to lacquer the board after it is running and once fully populated I can see the board being a little busy to work on. So I will add a couple of spare FETs

I miss understood the implications of the 0ohm I have reread the discussions on this and I will use them.

Sensor curve is approx

-10C 9200ohm
0C 5800ohm
20C 2500ohm
40C 1200ohm
60C 600ohm
80C 200ohm
100C 175ohm

I have been searching the forum for info on sensors setup and not come up with much concrete. So though I would use the stock bias resistor and rely on Freetherm to get the sensors reading back right. Now you mention 'sensor curve' (must have been having a mental block not to think that earlier) I have done a search and found your data for Nippon Denso sensors they look close, are they close enough?

I wont be climbing mountains but I had read somewhere on the forum about the benefits of a septate AAP, the extra error recovery seems worth the price.

Thanks

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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Fred »

Do you plan to run missing tooth + wasted spark + batch on two channels?

The extra FETs need to be connected to a CPU pin, and which pin you do that with depends on your intended use. If the above config is correct, then there are no spare pins on current firmware for injectors. In future, though, there may be code of a suitable quality (none exists right now) to use other pins for these tasks. On the other hand, if you plan to use an idle valve or some such PWMable thing, port P is a good choice. For future use Port B is as good a choice as any. For right now, your main two FETs should be connected to T6 and T7.

You also have 4!(thought it was 3 for a second, yay for 0.7!) lighter duty FETs which are more than heavy enough for idle valve and relay use, etc. And a high side, too!

Use your desired bias resistor, it's fine. The exact value only places the maximum linearity and resolution in a certain temp range. Aside from that, lower values heat the sensor internally, more. I'd say Denso is not close enough, and they all vary, so eventually I'll recommend everyone calibrate their exact sensors for max accuracy anyway. Go forth! :-)

Re AAP, I see you're in the midlands of England, a country devoid of any real mountains :-D It's nothing more than interesting for you, really. It can't do anything significant unless your altitude changes a lot. I'm yet to drive up anything really high, but NZ is pretty steep in general, and I don't really need mine. I do like looking at the curves, though, I can trace my route by the ascents and descents!

Here's a screen shot of my drive to work. Note the range of pressures is 99.67kPa to 100.86kPa which is really negligible IMO. Each step is an ADC step, IE, that's the granularity of it. The highest pressure is close to sea level (within sight!), and the lowest at the highest altitude I hit. This is probably similar to your lake district, I guess.

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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Ruffcut »

Hi, yes I realized I would have to wait for the firmware to do a duel injector setup but I have many projects on the go and its a vague idea at the minute so I don't mind waiting for that.

Yes will be driving an idle valve with one of the FET drivers, I will have to think what to do with the rest.

What has interested me with the AAP is if the ECU suffers a reset while the engine is running the ability to keep running without getting confused about the ambient pressure. Have I understood this correctly?is this as useful as I think it is? Is that for a future version of firmware? The motor that the ECU is going in is a off-road motor and the events that I compete in it are usually only a couple of mile stages so there is very little room to go up and down to much so altitude adjustment is not a concern.

Thanks for your help

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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

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Ruffcut wrote:What has interested me with the AAP is if the ECU suffers a reset while the engine is running the ability to keep running without getting confused about the ambient pressure. Have I understood this correctly?is this as useful as I think it is? Is that for a future version of firmware?
That would be useful if the alternative was idiocy. IE, if one assumes they can read MAP and get AAP just because they're fresh out of boot, one needs a kick in the nuts. The alternative, and currently the only way, and in future, the default, is to simply not compensate at all. It's not compulsory. In your case, and in mine (at the moment), it's not necessary, either.

IE, at the moment, the ECU does not care what ambient is, be it 102kPa or 9834908kPa or 0kPa, it acts the same. This value purely comes from the secondary sensor, no where else. Clearer? :-)

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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Ruffcut »

Hi,

Thats crystal clear now. I doubt I would ever get any real info from the sensor apart from maybe meteorological interest. Will order my parts tommorrow. Thanks.
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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Ruffcut »

Hi,

Just updating, been a while I have had a problem that got me a little dishearten . I managed to install the MCU the wrong way round, I dont quite know what I was thinking and mistook one of the plastic casting marks for the pin 1 mark, manly I was rushing. Only realized after soldering it all up and checking that none of the pins were shorted, no problem I though I will just use a heat gun and as I had a few days off work I though I would use the one I have at home more suited to paint stripping than anything else, rather than the fancy settable one with masks for chip removal we have at work. This was a mistake I managed to burn the board a little, so I put the board in a box and did not do anything with it for a bit, thinking I could use the majority of the components next time there is a spin of the board. But a couple of weeks ago I though I may as well install the MCU the right way round and see if it work, I checked the board out and all of the tracks did not seem to damaged, it just looks charred . I installed all the components on pages 2,3,7 and all the SMD ones.

After playing around with the software I have managed to get comms with the board using EMStudio in Linux.

I have a couple of notes that might help another newbie.
- Check and double check which way up the MCU goes.
- Be very careful if using a heatgun on your boards
- I have not managed to get Megatunix to work yet in windows FreeEMS radio button is grayed out and in linux it will not establish comms.
- On ubuntu 14.10 fresh install there were some library files not listed needed installing libgtkgl2.0-1 (or libgtkgl2.0-dev, I installed both at the same time) to get either FreeEMS-Loader or Megatunix to build I cant remember which.
- I am having to run FreeEMS-Loader and EMStudio with su or gksu to let them have access to the serial port. Is this normal?

Next job build I think I will build the input circuits and some kinda simulation circuits to check all that bit.

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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by Fred »

1) Forget MegaTunix
2) Add your user to the dialout group and log out and in again

Good luck! :-)
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Re: Ruffcuts 0.7 Alpha Build serial number 13 for Rover V8

Post by ToxicGumbo »

sudo useradd -G dialout username

I don't know of a way to adopt the increased privs immediately, so you'll likely need to logout or reboot first.


-Jeff
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