RCU Forums - CDI gr8flyer55

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RE: CDI gr8flyer55

I know the designe and find here allmost the same schematic only modern and with a micro.
http://www.mini-cooper-clubman.de/html/umcdi.html
I want to use (....) this kind of HV schematic, you find the same designe in professional designes.
The only reason I 'm not sure to use it, is the high current this designes use.
Thats also a reason I want to replace the CDI I allready use on my bike.

RE: CDI gr8flyer55

Hi everyone.
I think that this code is more correct.
It is only the base curve.
Rising edge, Hall sensor input.
No kill switch.

RE: CDI gr8flyer55

Hi Nyemi, do have also for me the exelsheet to generate the curve ?
The sensor is 40 degrees BTDC located ?
Into this code there are stil two tables, is this correct ?

RE: CDI gr8flyer55

Yes, Jake is an excel sheet, it generates all the data.
ASAP. Ask Jake, paste code excel sheet.

RE: CDI gr8flyer55

Nyemi, that is good thinking!

What's he's doing is disabling the sensor interrupt after it is activated. This way the sensor interrupt is disabled between the time the sensor is tripped until it finishes firing the spark. The way I had it written there is the possibility that the sensor interrupt could be triggered multiple times while the magnet was near the sensor.

If the sensor input is noisy then it could be triggered multiple times, and each time it would load a new delay value. I'm not sure that this actually ever caused any problems, but it could make the timing wrong or variable over the duration that the sensor was activated. That could make the timing a deg or two late on some revolutions if the sensor input was noisy.

This is a smarter way to manage the interrupts. Thanks Nyemi!

I have found the ignition to be very reliable in it's timing. This code improvement should take out a degree or two of jitter if the sensor input is being noisy. I'll hopefully post a video sometime this weekend to show how the ignition is functioning.

To time my engine I use two easy methods. First I hook everything up and slowly turn the engine until the LED flashes. I look at what degree this happens at and this gives me the rough hall position. Then I punch that number into the spreadsheet hall setting. Next I make a flat curve that is set for near the factory advance. Flash that and run it on the engine.

Now with a timing light I look at what the actual ignition advance is running at. If there is any difference in the set timing vs the measured timing I then adjust the hall setting to correct it. Mostly I am finding that it is no more than 1 digi-degree off. Once that is set correctly I load whatever curve I am experimenting with.

I have found that the program works right. It will track the RPM and fire with the right advance over the whole RPM curve.

This weekend I'll add Nyemi's change, take a video, and post a v1.0 release to the website! A big thanks to everyone who has helped on this project!

The next step is to work on the 1840 code. The 683 is at the limits of what it can do I think. Running two tables and having a kill switch are good features and it accomplishes everything a good CDI program needs to.

With the 1840 I'll add on-the-fly calculation of the entire advance curve and serial communication. I like the link Gompy posted to the solid state CDI design. I think the transformer design we use now works great, but alternate designs are always cool to experiment with. If we want to switch to an Atmel processor, that will be no problem. Right now the PIC seems to be working well. The 1840 will run at 32 MHz, providing 8 MIPS of processing power. Many of the Atmel chips will run at 20 MHz and provide 20 MIPS of power. I learned the PIC just for this project and I'm not terribly attached to either company's processors. Before I would have preferred Atmel, but now that I've learned PIC programming I don't really care that much. PICs are cheap and currently they seem to provide good processors in the 8-pin DIP packages. I'm working towards a dual-processor design and like the idea of using two 8-pin PICs as opposed to SMT or larger package choices. The PICs have better package choices for what I plan on doing IMHO, and the only real reason I see for switching to Atmel would be if we needed more processing power. I think 8 MIPS is probably more than enough (compared to the 2 MIPS we're using now). It seems like just about the right amount for what we're doing, and I think PICs are a little more durable.

-Jake

RE: CDI gr8flyer55

Quote:

ORIGINAL: nobitaemon

Hi,<div>If anyone can help me.</div><div>I want to make use ATmega8 Programmable CDI</div><div>and the C language.</div><div> </div><div>Thank you,</div>

First off, welcome to the project! You'll find some very smart people here.

I might be able to help you with some advice, and you can look over my code. But right now we're using PICs. They come in convenient packages for our application and seem to work well.

If I were you, I'd just buy a $10-20 PIC programmer and work from the code we're using. It took quite a long time to construct the spreadsheet for generating the timing table and to write the code. I've got a lot of advanced features planned, so this project is moving very fast. John has the hardware worked out quite well, and has kits available for very cheap prices.

Everything might seem confusing at first because we don't have all the documentation and instructions worked out, but things are working well. The hardware and software both work well, and it isn't hard to get started. PM or email John (gr8flyer55) and he can set you up with the hardware. Nyemi and I both have firmware for the PIC that work well. I know the thread has gotten pretty long, but it is worth reading, and you can see what we've done.

-Jake

RE: CDI gr8flyer55

I'm working on a HV-board we can control.
No HV when we given a spark and no more load if the capacitor is loaded.
Fast loading, 75 - 100 kHz and some more power up to 75 - 100 mJ to use with RC race engines.

Race engine have a high compression and need more mJ.
This designe is OK for 3 or 4 bar, but race engine have 8 bar and high pressure kill the spark.

But just like software do, it takes time to designe a good working HV-board.

RE: CDI gr8flyer55

I compiled Nyemi's edited code. It only works correctly if you ground pin3. This means there is no longer a functioning kill switch function.

John

RE: CDI gr8flyer55

He must have accidentally screwed something up somewhere, it's easy to do. The interrupt handling improvement is a good idea though. I'll have it incorporated tomorrow.

As far as I can tell from my tests everything is working exactly as intended. Nyemi's improvement can only help.

-Jake

RE: CDI gr8flyer55

In Nyemi's post with the attachment of the source code it states "No kill switch".
Reading the pin assignments in the source, it says pin 3 tied low. Looks to me that it was eliminated as a function.

John

RE: CDI gr8flyer55

Hi John

I'm sorry.
I'm back, kill switch routine.
You be careful.
I tested.
The input of dirt, it creates the power.

RE: CDI gr8flyer55

There must be a resistor to + power of 1 kOkm to keep the pin high and 100n to ground to filter the swtchmoment.
The pin is now open and pickup dirt.

RE: CDI gr8flyer55

Thank you Nyemi !
Now we have a choice of 2 versions. I needed the kill switch option for my use.
And thanks go to Rob for his filter suggestion, it works Rob ! Just tested your filter for the switch....no more problems!

John

RE: CDI gr8flyer55

Same to the table switch, put a resistor between power and the pin to keep the pin high.
Inside the PIC there are also pulldown resistors, but they don't work allways.
If using the intern pulldwon resoistor there will be over the pin and ground a resistant, a spike Voltage can set the pin high.
When pin high, the pin is switching, thats not wat you want, so make the pin high with a real resistor.

RE: CDI gr8flyer55

Hi John
I'm glad I could help you.

I ask you, circuit diagram.
What you're using the new software.
Because 100nF capacitor, high value, the Hall input.
Fair good value: 2,2nF-10nF
The 100nF capacitor:Change ignition timing value.(Delays in the Hall signal)!!!!
Circuit me, so working. See the picture.(I am using:4,7nF+4,7Kohm, LED, resistor, not necessary.)


You circuit, what works?

RE: CDI gr8flyer55

Nyemi, I am using a ready made ignition board, I only have to solder parts to it. I have no real schematic, but is the same as RCexl version 2 ignition. I will draw one as soon as I get time. Right now, doing repairs for customers, very busy.
Timer board is what is posted in the forum, ignition is basic RCexl CH ignition and are reliable.

John

RE: CDI gr8flyer55

I see. Thank you.
Your circuit is working, Jake Code?
There is no problem?

You feel the difference between the two codes?
I take criticism.http://www.rcuniverse.com/forum/js/f...eeth_smile.gif

RE: CDI gr8flyer55

Nyemi, your code is working very good!
Jake's code sometimes makes a misfire at high speed and timing changes slightly. Both work but your sensor input routine is more reliable for this circuit. I added Rob's switch filters to be sure of no problems and it works nice. Good job ! :-)

John

RE: CDI gr8flyer55

Slowly we finish the project, the time will be there for a real schematic and PCB.
I can't draw "something" and don't want to read 792 post back to see wat will be changed.

I want to start with the timerboard and "connect" the HV-board to it.
If some one will break the boards, HV and timer serperated, it must be possible.
Also for repair it can be very easy to break the boards a part.
Or make a sandwitch PCB to safe space into your box.

RE: CDI gr8flyer55

I know it's kind of late in the work but, has anyone looked at this web site? transmic.net/en/home.htm.
Gompy might be interested in this site because it is mostly about bike CDI's.
It does have a lot of ideas with PIC's and Atmel MCU's.

Ray

RE: CDI gr8flyer55

I can given you 50 more sites of CDI after 40 years work on it :D
Most CDI's on internet don't work, you need a couple of good people like we have now to make a good CDI.
PIC / AVR software is old or is not opensource, even so the hardware......all secret in epoxy boxes.
We want to make a CDI / TCI you can use with any engine, only changing the software / hardware.
The biggest problem is a reable HV-board with enough power and more professional.
It have to use less power, switch off when spark and switch off if ignitioncapacitor is full loaded.
If you put a candle under pressure the spark will be smaller if the pressure will be higher.
Our engines are low pressure, only race engine (they have allready a CDI) are high pressure.
We want also something more witch cheap factory ignitions don't have, like realtime monitoring.
We can all buy a cheap, 25 US$, CDI and our engines run better.
But I think when we can do more with the CDI and program, we can let the engine run like a rabbit [>:]
If we can make the CDI small, we can also make it bigger.......and can use them for real (mini) bikes / carts / aso.

BTW 1, my father was offroadracer, I grow up with a world champion (Hans Spaan) and my fist project I send to a electronicmagazine was in 1972, a transistor ignition and win a multimeter with the designe :eek:
There was good thinking about the prices......now one of the winners have thoose equipment, we al build with a wet finger [:-]

BTW 2, there is only one problem.....I stock in 2stroke, thats wat I like !

RE: CDI gr8flyer55

Hi John
Thank you for your response.
To you ignition curve idea.
I create for you.http://www.rcuniverse.com/forum/js/f...sn/thumbup.gif

Sure.
Everyone who wants to custom curve.

RE: CDI gr8flyer55

Thanks Nyemi. I'll need one good curve for 4 stroke engines. I'll try whatever you make.

John

RE: CDI gr8flyer55

Wat about a Exelsheet realtime online ?

BTW John, this was the picture I try to sent to you.

RE: CDI gr8flyer55

[youtube]http://www.youtube.com/watch?v=E258qUJlOdU[/youtube]