Go Back   EcoModder Forum > EcoModding > Instrumentation > OpenGauge / MPGuino FE computer
Register Now
 Register Now
 


Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 05-15-2008, 11:34 PM   #61 (permalink)
MP$
 
diesel_john's Avatar
 
Join Date: Jan 2008
Location: SW Ohio
Posts: 591
Thanks: 5
Thanked 14 Times in 12 Posts
Send a message via MSN to diesel_john
Smile

The VSS signal from the transmission transducer on my '91 Ford is fairly weak. In fact, a couple months ago, the connector at the trans had gotten oil in it and that was enough to pull down the signal. I don't think i have a wire from the ECU to the speedo because i have a speedo cable too.

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 05-15-2008, 11:45 PM   #62 (permalink)
dcb
needs more cowbell
 
dcb's Avatar
 
Join Date: Feb 2008
Location:
Posts: 5,032

pimp mobile - '81 suzuki gs 250 t
90 day: 96.29 mpg (US)

schnitzel - '01 Volkswagen Golf TDI
90 day: 53.56 mpg (US)
Thanks: 156
Thanked 264 Times in 207 Posts
Just FYI, the debug screens are accessible via the left right buttons now, as is a "Demo mode" if you press both left and right together once (cycles back and forth through pre-recorded data). So, the data is all there, it is just a matter of presenting it now (and you don't even have to get your hands dirty now). I don't know actually what mpg values it should be, but I'm guessing the end of the array data is 45mpg @ 25mph instant.

The other button combinations are:
middle: brightness
middle+left: Tank Reset
middle+right: Current Reset

The previous patched version debug screen may be out of date, so make sure to use the latest from post 1.
__________________
WINDMILLS DO NOT WORK THAT WAY!!!
  Reply With Quote
Old 05-15-2008, 11:51 PM   #63 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 20,776

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
Last 3: 51.27 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 60.34 mpg (US)
Thanks: 2,632
Thanked 5,537 Times in 2,840 Posts
Way to go, dcb. Very cool to watch things unfolding.

I'm going to get in on the fun next week with mine.
__________________
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
Old 05-16-2008, 02:34 AM   #64 (permalink)
dcb
needs more cowbell
 
dcb's Avatar
 
Join Date: Feb 2008
Location:
Posts: 5,032

pimp mobile - '81 suzuki gs 250 t
90 day: 96.29 mpg (US)

schnitzel - '01 Volkswagen Golf TDI
90 day: 53.56 mpg (US)
Thanks: 156
Thanked 264 Times in 207 Posts
Thanks Cap'n

So how do I have 64 bit math on the arduino without the 7k libraries. I can't declare one long long without running out of space. But need to do some accurate multiplying/dividing that would benefit from the extra bits. Does anyone know of any short and sweet 64 bit math routines handy that take less than 7000 bytes?
__________________
WINDMILLS DO NOT WORK THAT WAY!!!
  Reply With Quote
Old 05-16-2008, 08:46 AM   #65 (permalink)
dcb
needs more cowbell
 
dcb's Avatar
 
Join Date: Feb 2008
Location:
Posts: 5,032

pimp mobile - '81 suzuki gs 250 t
90 day: 96.29 mpg (US)

schnitzel - '01 Volkswagen Golf TDI
90 day: 53.56 mpg (US)
Thanks: 156
Thanked 264 Times in 207 Posts
Well, if I trim down my demo mode so it just uses constant values I can get the 64 bit library to fit (things start breaking before you get to the maximum), so we are officially tight on space and might even need to pare down a couple things, but nobody has to write and debug and integrate any 64 bit math routines for version 1.

Binary sketch size: 14030 bytes (of a 14336 byte maximum)
__________________
WINDMILLS DO NOT WORK THAT WAY!!!

Last edited by dcb; 05-16-2008 at 09:34 AM..
  Reply With Quote
Old 05-16-2008, 10:05 AM   #66 (permalink)
EcoModding Apprentice
 
awillard69's Avatar
 
Join Date: Feb 2008
Location: Streamwood, IL
Posts: 105

Dakota - '00 Dodge Dakota Club Cab, Sport
90 day: 18.57 mpg (US)

Jeep - '01 Jeep Wrangler TJ Sport
90 day: 18.46 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
That would be reason to evaluate your code and see if there are any optimizations that can be done, any old school tricks to eliminate instructions in the compiled code. May need to dig into the compiler to see if there any optimizations that can be leveraged there.

I'm not sure you will need the 64 bit data, you could get more than .1 variation from a signal (timing, weak/faulty unit, etc), so having resolution beyond one decimal may not be helpful and in this case detrimental to other features desired.

BTW, I just got my *duino and display. So, I'll get to assemble it and do my "Hello World" test. Something to do this weekend!

Also, I was thinking of putting together a simple circuit, something based on a few 555/556 chips to provide a generator for test signals (static injector and VSS pulse trains) to allow bench testing of the code without having to deal with the connect issues. I don't have a scope, so I'll have to rely on just the math for the apparent frequencies and pulse widths. Unless anyone has any other ideas...?
__________________

  Reply With Quote
Old 05-16-2008, 11:24 AM   #67 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 20,776

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
Last 3: 51.27 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 60.34 mpg (US)
Thanks: 2,632
Thanked 5,537 Times in 2,840 Posts
awillard: great - another beta tester signs up!

I believe the list of beta testers/second fiddlers now includes:

larrydag - '95 Honda Accord DX
myself - '98 Pontiac Firefly (Geo Metro)
andrewj - '94 Civic CX
mosier - ??
awillard69 - ??
Mr Clean - ??

And of course our fearless leader:

dcb - 97 saturn s2

Did I miss anyone?

dcb: I wasn't aware of the sketch size limitation. Way to squeak 'er in there.

The size challenge reminds me of the5k.org... which now sadly appears to be defunct. It was a great web site where contests were held to build the best web pages that came in under, you guessed it, 5kb. There was awesomely creative stuff there at one point. I'm sure there are other sites like it out there.
__________________
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
Old 05-16-2008, 12:11 PM   #68 (permalink)
FuelSipper
 
Join Date: Mar 2008
Location: Dallas, TX
Posts: 99

HondaHokie - '95 Honda Accord DX 4 door
90 day: 26.91 mpg (US)
Thanks: 0
Thanked 8 Times in 3 Posts
I had the debug mode on this morning as I drove into work. I pretty much saw the same results. Injector %D would jump around from 0 to 40% approximately. Although it seemed to go to a very large whole number occasionally (23456 maybe)? I don't know if that is a bug or something. The C would just jump to 0.0, 0.1, 0.2. Don't know if that is accurate but sure doesn't look like an rpm. Maybe needs to be multiplied by 10000 in the code.

Nothing with VC. I'm thinking it might be the connection circuit because I definitely get a reading with the multimeter albeit a small one. I don't think the signal goes above 0.4-0.5 Volts. What kind of signal are we supposed to get with the VSS?
  Reply With Quote
Old 05-16-2008, 12:46 PM   #69 (permalink)
dcb
needs more cowbell
 
dcb's Avatar
 
Join Date: Feb 2008
Location:
Posts: 5,032

pimp mobile - '81 suzuki gs 250 t
90 day: 96.29 mpg (US)

schnitzel - '01 Volkswagen Golf TDI
90 day: 53.56 mpg (US)
Thanks: 156
Thanked 264 Times in 207 Posts
The "%D" tells me you don't have the latest and greatest. I would start with the latest code from post 1.
__________________
WINDMILLS DO NOT WORK THAT WAY!!!

Last edited by dcb; 05-16-2008 at 07:08 PM..
  Reply With Quote
Old 05-16-2008, 04:59 PM   #70 (permalink)
EcoModding Apprentice
 
awillard69's Avatar
 
Join Date: Feb 2008
Location: Streamwood, IL
Posts: 105

Dakota - '00 Dodge Dakota Club Cab, Sport
90 day: 18.57 mpg (US)

Jeep - '01 Jeep Wrangler TJ Sport
90 day: 18.46 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
Thumbs up

Quote:
Originally Posted by dcb View Post
So how do I have 64 bit math on the arduino without the 7k libraries. I can't declare one long long without running out of space. But need to do some accurate multiplying/dividing that would benefit from the extra bits. Does anyone know of any short and sweet 64 bit math routines handy that take less than 7000 bytes?
I couldn't wait for my board to get assembled, so I started playing with the latest code here at work.

I was able to shrink the sketch size from 7464 bytes to 6642 bytes (11% reduction) by just adjusting the data types used. For instance where you have
Code:
for( int x = 0; x < 10; x++ )
You can save space by converting it to
Code:
for( byte x = 0; x < 10; x++ )
It can be anywhere from 1 to 3 bytes, depending on system. Note: I cannot verify that any changes do not negatively impact the operation of the code itself.

Just changing the various loop control variables from "int" to "byte", I was able to reduce the size quite a bit.

Nextly, removing variables from the global scope has an even greater impact.

For instance, moving
Code:
int vsspinstate=0;
into the function where it is used saves 40 bytes! I think that maybe you planned to use it elsewhere, but are not currently. If you don't intend to use it, trim it completely and save the space altogether.

Now that I look deeper into the code, not that I understand everything you build so far, you are using some OO constructs (LCD and trip classes). You may also be adding overhead you don't expect and may gain some significant space by converting to structures and functions. Anecdotal perspective: there is no OO/C++ in the Linux kernel (per Linus) because of the overhead in complexity, size and speed - performance is critical. OO is for the programmer, not the processor/CPU.

Let me know if you want to see my modifications. Since you are up and running, you may be able to evaluate their "properness" better than I can at this point.

It's nice to be more than the sum of our individual parts - together we are stronger.

__________________

  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
My kingdom for a giant, heated workspace MetroMPG The Lounge 14 12-12-2010 09:08 AM
Motorcycle manufacturers beginning to release MPG info MetroMPG Motorcycles / Scooters 1 04-03-2008 05:23 PM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com