Programmable Open Source CD Ignition PIC1840 - Page 8 - RC Groups
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View Poll Results: Whatís the most important thing to you?
Lowest possible cost 3 23.08%
Make it as small and light as possible 6 46.15%
Battery longevity is very important 3 23.08%
Highest power possible 3 23.08%
Highest RPM possible 2 15.38%
Only use through hole construction 2 15.38%
No winding of transformers 4 30.77%
Group buy of components including boards 0 0%
Group buy of boards only 1 7.69%
Iíd rather buy a kit with everything in it 0 0%
I want to buy a pre-built & pre-programmed system 0 0%
I only want to use a 4.8v Ni-MH battery 2 15.38%
I only want to use a 2S battery 1 7.69%
I only want to use a 3S battery 1 7.69%
I want to use a 4.8v battery to 3S battery 5 38.46%
I want to use only off the shelf parts from Digi-Key or Mouser 3 23.08%
I want the Timer board to be separate from the HV board 6 46.15%
I want a combination Timer & HV board 1 7.69%
I want all the options possible using jumpers 3 23.08%
I want a USB connection 2 15.38%
I want a serial connection (DB9) and Iíll use my own USB adapter 3 23.08%
I want a ICSP connection 3 23.08%
I want a premade parts list (BOM) at Digi-Key 2 15.38%
I want a premade project parts list (BOM) at Mouser 1 7.69%
I want 1 design and 1 design only 1 7.69%
I want optional designs to choose from and Ill make the boards myself 8 61.54%
Multiple Choice Poll. Voters: 13. You may not vote on this poll

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Jan 10, 2013, 02:13 PM
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Nav_Aids's Avatar
Originally Posted by jakestew
New spreadsheet versions posted on the website!

A big thanks goes out to Ray Richter (Nav_Aids) for creating these versions!
Thanks Jake but you did the bulk of the spreadsheet, the hard stuff, I'm just tweeking it.

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Jan 17, 2013, 06:57 AM
Inventor&Genius Extraordinary
tune by tito's Avatar
Long time ago(circa 1998-2003) when I was a "SITH"(Sorry but with the new Disney deal I Returned to be a "Jedi") I did develop a Programmable CDI for Mini ATV and motorcycles. I will like to see it been develop farther into today technology like Android Phones and USB.

Best Regards Tito
Jan 19, 2013, 01:16 PM
Registered User
Nothing new for our dead ended project.
I am still getting ignition cut off after 4,000 rpm. Board power is still there, just quits sparking.

Jan 19, 2013, 11:42 PM
Registered User
When did this start? Last I heard everything was working fine up to at least 14k RPM.
Jan 22, 2013, 11:12 AM
Registered User
Jake, I found the problem. Bad pic chip. I think it got zapped on my workbench with all the wires I have laying in my test area next to the ignition coil. I had it working fine, then heard sparks somewhere besides the coil. Figured I'd try a fresh chip and curves and found the chip wouldnt take a program. Working ok now.
Any updates on the 1840 chip programming?

Jan 22, 2013, 01:21 PM
Registered User
I've been pretty busy with work, but I think I'm close to getting the OTF method working right. I'll be testing on my engine sometime this week. I'm waiting on my buddy to get a new tank of gas and weld up my new exhaust system. When that's don't I'll be able to run in the house and inside the shop, so that should make things a lot easier. It's pretty cold at the moment here to be working outside for any length of time.
Jan 22, 2013, 01:32 PM
Registered User
Nav_Aids's Avatar
Originally Posted by jakestew
.....It's pretty cold at the moment here to be working outside for any length of time.
How cold is cold Jake? It's cold here -31C/-23.8F with the windchill it's -40C/F

Jan 22, 2013, 01:55 PM
Registered User
Originally Posted by Nav_Aids
How cold is cold Jake? It's cold here -31C/-23.8F with the windchill it's -40C/F

LOL, even I know I'm being a crybaby. I used to live in Minnesota and this is T-shirt weather compared to winters there.

Guess I'm habituated to the easy winters here by now. It had been somewhat cold here, but was just over freezing the past two days.

The main thing is my exhaust. I used a piece of aluminium plate to adapt the Homelite exhaust to a 50cc scooter exhaust pipe, which I cut off right after the bend. Then I welded on two lawn mower style mufflers, one skinny long one and one short fatter one. It works well, but my buddy ran out of gas and there are a couple leaks in the thing still. A two-stroke CAN be muffled down to sound like a 4-stroke, and my end muffler even stays cool to the touch. It's not suitable for flying the way I have it, but it should work good for my fan-boat/sled project.
Jan 22, 2013, 02:16 PM
Registered User
Nav_Aids's Avatar
I remember you saying you were from Minnesota, northern Minnesota has a windchill warning out also right now. Wish I could get a job in Hawaii, not to cold, not to hot.

I forgot to tell you, when I was a kid I made a Cox .049 air-boat that I use to run in the winter. It was free running so it was neat to watch it go all over the place, have fun.

Jake, do you know how many clock cycles it takes to do a read from the EEPROM memory in the cpu?

Jan 22, 2013, 02:32 PM
Registered User
I think the reads are pretty fast. Write or erase takes 4-5ms.

IIRC the reads are tied to the clock, but write times are related to a certain amount of time and are pretty slow.
Jan 29, 2013, 12:20 PM
Registered User
Gompy's Avatar
Have fun.
Last edited by Gompy; May 05, 2013 at 06:04 PM.
Feb 01, 2013, 10:13 PM
Registered User
Rob, looks like you have some perfect tracking now with that video. Problems all solved for now?

Feb 04, 2013, 07:24 AM
Registered User
Nav_Aids's Avatar
Excellent work Rob.
By the way what Android software is that you are running? it looks handy.

Feb 08, 2013, 12:16 AM
Registered User
Jake, how are doing with the OTF data changes?
Testing more changes to curves and settings, and test engine is getting a real workout this week. I have what seems to be my best curves since I started all of the testing of version #1. MSD cutoff at 2300 is working as expected. There is sometimes a slight delay when closing the kill switch for a maybe 1 or 2 seconds at mid rpm ranges. Odd.... It does work, just a slight delay. Had a receiver operated cutoff thru the Bitswitch circuit which I thought was the delay, but after testing with a manual pushbutton hard wired to the timer board, I got the same delays. It is not every time though, also odd. I can use my other direct CDI board kill and might just switch over to that one with the Bitswitch circuit instead.
I have some commercially made board samples. One for my old CDI board and one for the original timer. Both considerably smaller than my originals.

Feb 09, 2013, 02:25 PM
Registered User
I'm trying to work out the hall delay factor so that the code can calculate for that. Hopefully I'll have a beta version sometime this week.

I still have to make up a spread sheet and figure out the final method of how the curves are defined. Right now I'm still running with a fixed advance. But it seems like things will pan out and the code will run faster and more accurately. Hopefully the RPM limit problem will also be worked out from the same changes.

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