Wideband setup through apu1

[donf]

Math is here http://www.gearhead-efi.com/Fuel-Inj...eband-Question

Conversions for 256 bit 0 to 5 volts!

For the LC-1 WideBand 0V = 7.35 AFR and 5V = 22.39 AFR.
AFR of 7.35 to 22.39 is a difference of 15.04 divided by 256 = 0.05875

Conversion for this would be:
(X * 0.05875) + 7.350000
Adding the offset makes 0 volts 7.35 AFR

For other Wide Band controllers that have 0V = 10.00 AFR and 5V = 20.00 AFR.
AFR of 10.00 to 20.00 is a difference of 10.00 divided by 256 = 0.0390625

Conversion for this would be:
(X * 0.0390625) + 10.00000
Adding the offset makes 0 volts 10.00 AFR

So... for my AEM 30-3010 we will follow the logic step by step from above.
OK so from the above we need 0 and 5v numbers.

Formula for the 30-0310 from the Install manual page 6
0-5V Analog output
AFR = (2.3750 * Volts) + 7.3125

7.3125 = (2.3750 *0) + 7.3125
19.1875 = (2.3750 *5) + 7.3125
Conversions for 256 bit 0 to 5 volts!

For the AEM 30-0310 Wideband 0v = 7.3125 AFR and 5V = 19.1875
AFR of 7.3125 to 19.1875 is a difference of 11.875 divided by 256 = 0.04638671875

Conversion for this would be:
(X * 0.04638671875) + 7.3125
Adding the offset makes 0 volts 7.3125 AFR

This is for running direct to the ECM. Not the other.

[Stokes1114]

Thanks for breaking that down, helps me understand it much better now. I am going to be able to try it out later today after the boys soccer game. Do you guys know anything about the payload size, of how to figure it? My adx says payload size is 63, which would be 62 if starting from 0. In Mark's tutorial, it says it would be 63&64. So I should use 63 for that? I think it's 63 and 64 bc we have 2 bytes. Trial and error will work I suppose, just trying to understand it all. Thanks for all your help fellas
Dustin

[donf]

Thanks for breaking that down, helps me understand it much better now. I am going to be able to try it out later today after the boys soccer game. Do you guys know anything about the payload size, of how to figure it? My adx says payload size is 63, which would be 62 if starting from 0. In Mark's tutorial, it says it would be 63&64. So I should use 63 for that? I think it's 63 and 64 bc we have 2 bytes. Trial and error will work I suppose, just trying to understand it all. Thanks for all your help fellas
Dustin

If you are not running direct to the computer do not use mine. I put the math there then found the post above explaining the formulas are different running the interface you are running. I still do not understand the reasoning for trying to do anything other than just hook it direct as it works so well.

[Stokes1114]

I was mainly doing it for ease of install. I have the autoprom mounted under my dash semi permanently so I can make changes quick, anytime I want. I don't have to repin anything, just add the 2 wires to it. But as Steve said the autoproms channels are 1024 bits so more resolution, and once I figure this out I can add any other sensors I want to log. It has 3 channels that show up in the same log. After I get this working I really want fuel pressure in as well. I think with the help I'm getting on here I should be able to get it going, but it's good to know I can always run it straight to pin b-16.

[donf]

I was mainly doing it for ease of install. I have the autoprom mounted under my dash semi permanently so I can make changes quick, anytime I want. I don't have to repin anything, just add the 2 wires to it. But as Steve said the autoproms channels are 1024 bits so more resolution, and once I figure this out I can add any other sensors I want to log. It has 3 channels that show up in the same log. After I get this working I really want fuel pressure in as well. I think with the help I'm getting on here I should be able to get it going, but it's good to know I can always run it straight to pin b-16.

I can do changes with whatever the other moates emulator is called. I have had it corrupt the program a few times without warning so I am hesitant to use it out of walking distance. I guess I could always carry the fixed parts with me. Ether way the wide band can be hooked direct if you decide to go that way. As far as finer resolution, the computer you are tuning is still the same, so not a whole lot changes. It was like the ADX I started with. It had columns in the history fuel tables that were not in the bin, someone thought they would be fancy. It looked impressive and you did get more information, but it was useless. After accidentally copying the useless columns into the spreadsheet a few times, I got rid of them. Now its a no brainer, you can copy all data from one sheet to the other. Its fast and easy.

[steveo]

i'm all about chucking unnecessary data precision, but if you can have 0.01 afr steps instead of 0.05 because you got nice gear, why not? (this is roughly the actual difference in resolution here)

it's actually easier to use the APU1's inputs, he just hasn't figured it out yet.

[Stokes1114]

Had a chance to mess with it for about an hour yesterday. I was not able to get any close results with my gauge. I tried going to the other 2 channels and adjusting the packet size with no luck. I did have a 7 year old pulling on my leg to go play the whole time though lol. So hopefully tomorrow evening I'll be able to try again and record it and take notes.