hey so i just purchased a aem 3.5bar map sensor... and it just hit me we have no SD xmls for it ... (the price was sooo good), no ive search still nothing mayb i dont know how to word it " how to creat xml equations ?" lol. but i found the aem pdf with the vlt vs pressure values for the 3.5 bar now im curious as to how to turn the in to "x*blah" in ecuflash for SD w/ v7 or v5 and logging purposes in evoscan . thanks guys 4life

also it would be cool to have a stiky/write up on how you guys go about calibrating these electronics/sensors.. thnx.

 

ok just downloaded the ecuflash xml for SD v7 .. stupid me they are there already... now just for the evoscan....

 

The equations are literally right in the xml. Just copy the correct equation from ecuflash to evoscan and make sure your output is logical.

 

ok there are alot of numbers.. i mean i wanna learn but im being pointed in very vague derections... i know thet the aem 3.5 bar map is 0.5v is -14.7psi 4.5v is 35.3psi its linear, i also know that 0v =0 and 5v =255 but im lost there how does all that translate into 0.(numbers)*x ? please im no math wiz or coding pro.. but you help would be greatly apreciated. i would hate to have to try and sell this map sensor....

 

50/229x-14.7

 

genius! thnx. if you dont mind how did you get that?

 

x(5-0)/(255-0) = 4.5
x/51=4.5
multiply both sides by 51
x = 229.5 i.e. 229 or 230 is the closest integer

now
ax+b=y
we want to get a, b from that for known x,y
a.229+b = 35.3
a.0 +b =-14.7
so b =-14.7 let us take it to the first equation
a.229-14.7=35.3
add 14.7 to both sides of the equation
a.229=35.3+14.7
a.229=50
divide both sides of the equation by 229
a=50/229
hence
50/229x-14.7 = y, your equation.

 

LOL, theres your answer.

Great job acamus.

 

thnx!

 

It is called System of linear equations in elementary algebra. Hope you have found a mistake/approximation that I have done :P

 

nooo i didnt.... i have my calculator in hand lol and im like what mistake did he make on purpose lol.

 

wait ur suppose to round up to 230 instead of using 229 rite?

 

Nope, I have overlooked 0.5V
Now you can calculate the correct one
(Hint: 50/204x-20.8)

 

assuming the hint isnt the actual equation im gonna grab my calculator and report back. i really appreciate your time as well, so many things are thrown around in a "take it , and believe it" fashion... even if i may never be able to fully grasp alot of the number aspect of this ecu coding at lease its there..

 

ok i understand the 204 its the delta of the slope in the 0-255 form but what is the 20.8 for?also im not getting a linear graph that falls betweet what were looking for when i graph it on the calc none of the y= vals move from out the negative psi.. from 0.5v -4.5v urg.. im a fool.. pitty me. im off to school now. ill be checking in on my phone.