Knock Detection with variable sensitivity over RPM

A forum for discussing the MegaSquirt related (but non-B&G) board development, assembly, installation, and testing.

Moderators: jsmcortina, muythaibxr

Locked
johnc32779
Experienced MS/Extra'er
Posts: 163
Joined: Wed May 05, 2004 7:17 pm
Location: Longwood, Florida

Re: Knock Detection with variable sensitivity over RPM

Post by johnc32779 »

HOODEY wrote: I need a better way to connect the LCD (16 pins) wish I could purchase a ribbon cable already solder to connector.
An interesting smart display with serial command capability that might meet your needs:

http://www.sparkfun.com/commerce/produc ... ts_id=8537

http://www.4dsystems.com.au/prod.php?id=84

John
BMW 1971 E3 Sedan; 1989 E34 M30 Engine, 60-2; 5spd-OD
davcol
Experienced MS/Extra'er
Posts: 160
Joined: Tue Dec 22, 2009 6:12 pm

Re: Knock Detection with variable sensitivity over RPM

Post by davcol »

HOODEY wrote:Finally upgraded processor two steps. Pic18f452 to pic18f4520 to pic18f4525.

It can log twice as much detonation data to ram.
Faster ADC capable of converting knock value to digital value in 12us down from 30us.

Next step will be creating a user manual as this device has become very complex.

Single channel ignition retard built in. When knock is detected timing is retarded until knock goes away.
Then the retard is slowly taken away.The LCD displays the amount of retard.
so will you be making this unit to sale to all the Megasquirt users and also will it work with MS for fine tuning the engine.
If yes to the above question then how affordable will this be :?:
m2 extra v3.57 3sgte full sequential injection V1.1A P&H Board
full sequential spark low current c.o.p.
holset turbocharger
HOODEY
Helpful MS/Extra'er
Posts: 115
Joined: Sat Feb 21, 2009 5:18 pm

Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Willing to sell as a kit
Last edited by HOODEY on Sun Nov 13, 2011 9:02 am, edited 1 time in total.
skyseb
MS/Extra Newbie
Posts: 1
Joined: Thu Sep 30, 2010 7:01 am

Re: Knock Detection with variable sensitivity over RPM

Post by skyseb »

WOOW!! :yeah!:

can you post the schematic for TPIC8101, I work fine with microchip microcontrolers, but my problem is in the analog hardware.

thanks
reliant_turbo
MS/Extra Newbie
Posts: 6
Joined: Thu Mar 10, 2005 8:28 am
Location: Warsaw NY
Contact:

Re: Knock Detection with variable sensitivity over RPM

Post by reliant_turbo »

hey guys,

i read earlier in the thread that the knock present pin on the MS gets read every 60ms? is this correct?

thanks

Brian
Brian Bucar

88 Plymouth Reliant K 2.5 Intercooled Turbo 5-Speed
02 Subaru Forster Winter Rat
02 Honda CR-V Turbo Project
420aRaf
Helpful MS/Extra'er
Posts: 59
Joined: Thu Feb 19, 2009 4:33 pm
Location: Staunton, VA

Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

That’s what I’ve been using and it works great that way for MS2. I would believe MS3 is much faster.
-Rafiel
reliant_turbo
MS/Extra Newbie
Posts: 6
Joined: Thu Mar 10, 2005 8:28 am
Location: Warsaw NY
Contact:

Re: Knock Detection with variable sensitivity over RPM

Post by reliant_turbo »

im not up on the MS2extra code aspect of things and how much headroom is left with the MS2 processor but i wonder if there is possibility of changing that input pin to trigger an interrupt. then you wouldnt need 60ms to make sure that the MS sees the knock signal. it would also lessen the ignition cycles/knock events before the MS begins to pull timing.

if the knock pin is triggered, say 1ms after it was sampled and all cyls are knocking, you could have ~6 knock counts at, say, 4000rpm on a 4 cyl before the MS even began to respond.... 12 if you were at around 8000 rpms on a 4cyl.

thats a fair amount of knock in my opinion.

Brian
Brian Bucar

88 Plymouth Reliant K 2.5 Intercooled Turbo 5-Speed
02 Subaru Forster Winter Rat
02 Honda CR-V Turbo Project
420aRaf
Helpful MS/Extra'er
Posts: 59
Joined: Thu Feb 19, 2009 4:33 pm
Location: Staunton, VA

Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

I don’t send a knock signal on every knock count because it will overcompensate my timing (comparing one TDC to the next). I do it based on knock counts after all conditions are right for knock. I will eventually upgrade though.

Because the knock pin is an ADC it will take longer, but I wonder if input PE0 or PE1 is faster.

http://www.msextra.com/forums/viewtopic ... =knock+pin
-Rafiel
HOODEY
Helpful MS/Extra'er
Posts: 115
Joined: Sat Feb 21, 2009 5:18 pm

Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

420Araf How is your project coming along? I will be looking forward to the PIC24f and C programming pretty soon.

I think I am pretty much done with development except for the occassional upgrade to the interrupt routine for specific vehicles.
420aRaf
Helpful MS/Extra'er
Posts: 59
Joined: Thu Feb 19, 2009 4:33 pm
Location: Staunton, VA

Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

It’s coming along good. :D I added an error checking tool for my crank and cam wheel. I have everything for the knock sorted fine but I switched again from a DSPIC24f@40MIPS to a DSPIC30f@30MIPS. (Main reason was 3.6v max on the ADC pins) I been spending some time with small OLED’s and LCD’s to view graphs/data, so I will add it sometime in the future. My current board is done with the 8x2 LCD and all connectors are done with ribbon instead of hard wire, I just have to make it. Will post soon.
-Rafiel
HOODEY
Helpful MS/Extra'er
Posts: 115
Joined: Sat Feb 21, 2009 5:18 pm

Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Can I see how you approach the LCD connectors?
420aRaf
Helpful MS/Extra'er
Posts: 59
Joined: Thu Feb 19, 2009 4:33 pm
Location: Staunton, VA

Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

I used a 14 pin 2 row header for the 8x2 LCD with a matching connector. There's not much to it. I haven’t made them yet; will post soon.
-Rafiel
HOODEY
Helpful MS/Extra'er
Posts: 115
Joined: Sat Feb 21, 2009 5:18 pm

Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

????
Last edited by HOODEY on Sun Nov 13, 2011 9:02 am, edited 1 time in total.
HOODEY
Helpful MS/Extra'er
Posts: 115
Joined: Sat Feb 21, 2009 5:18 pm

Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

????
Last edited by HOODEY on Sun Nov 13, 2011 9:03 am, edited 1 time in total.
paulpug
Helpful MS/Extra'er
Posts: 131
Joined: Wed Nov 11, 2009 9:12 am

Re: Knock Detection with variable sensitivity over RPM

Post by paulpug »

Hi Hoodey,
would it be possible to produce a simpler version of the sensor ,one that could be
incorporated into MS

Paul
HOODEY
Helpful MS/Extra'er
Posts: 115
Joined: Sat Feb 21, 2009 5:18 pm

Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Of course .I am currently working with ms enthusiast to create a kncok gaurd lite.

It has the same brains but less hardware and will into the ms enclosure.
paulpug
Helpful MS/Extra'er
Posts: 131
Joined: Wed Nov 11, 2009 9:12 am

Re: Knock Detection with variable sensitivity over RPM

Post by paulpug »

hi


do you have an eta and price?

Paul
maximuscr31
Helpful MS/Extra'er
Posts: 36
Joined: Sun Dec 26, 2010 5:00 pm

Re: Knock Detection with variable sensitivity over RPM

Post by maximuscr31 »

Very interested in this as well
HOODEY
Helpful MS/Extra'er
Posts: 115
Joined: Sat Feb 21, 2009 5:18 pm

Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

?????
Last edited by HOODEY on Sun Nov 13, 2011 9:04 am, edited 1 time in total.
420aRaf
Helpful MS/Extra'er
Posts: 59
Joined: Thu Feb 19, 2009 4:33 pm
Location: Staunton, VA

Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

HOODEY wrote:
I do it based on knock counts after all conditions are right for knock.
so what really is knock count?

Here is test on the nissan pathfinder vg33e v6. Knock Gaurd manual completed. http://www.youtube.com/watch?v=KDjHy_nXN-o

Dspic30f has 5 volt pins? What specific pic are you using and what programmer are you using to program it.
I use real ice and pickit3, and yes all dspic30 operate at a max of 5.5v.

To keep it simple I’m looking at the frequency and voltage differences in a certain window after TDC. I haven’t had much time to work on my new design, but I have worked on many different breakout OLED boards and COG units to display more info as the 8x2 display didn’t show enough info. (Leaning towards the COG units with SPI) Still a work in progress:

Image

Also found the pic I had with the DSPIC30 and ribbon cable connectors with LCD you asked me for (Dont have the ribbon connectors with me), however I scrapped this board and going to have a 2 layer made with more options sometime soon.

Image
-Rafiel
Locked