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evoscan rpm issue won't log past 7968.75

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Old Mar 19, 2017, 01:21 PM
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evoscan rpm issue won't log past 7968.75

hello friends, just seeing if any of you have had this issue and if so how did you remedy it?

background on this:
car is hitting the traps at about 8300 rpms and running 10.30's at about 140mph
in every log i have the rpm maxes out at 7968.75 and just stays there. it makes it really difficult to adjust the top end of the timing and fuel maps.
i did submit a support ticket to hamish. I was just hoping to get an answer quick, thought maybe it was a dumb issue I just wasn't seeing.

out the box the settings for rpm request id 21 the scaling is .01 and the min/max chart is 0 and 8 respectively and 0 and 80 for gauge.

I tried to adjust it to 0 and 11 and 0 and 110 respectively thinking that should give me 3000 rpm more resolution to see but I guess I was wrong. I guess i am stumped on this. I am sure it is something really dumb and easy to fix just cant see it
Old Mar 19, 2017, 01:27 PM
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I think i just figured it out.........



the eval formula is 31.25*X=rpm
so if 8000 rpm and you solve for x than you get 256
now if you solve for x on the max i am seeing and its 7968.75 rpm that gives you 255
so I'm assuming we are using a raw value of 0-255 to log rpm and using the eval to convert it.

so I guess is there a different was of seeing more resolution or another request id that I can log to be able to log above the 7968.75rpm??

Last edited by 01sporty; Mar 19, 2017 at 01:28 PM. Reason: adjusted my math numbers Typo
Old Mar 19, 2017, 01:45 PM
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admins delete if you want I figured it out. didn't see the 2byte rpm mod request in evoscan
Old Mar 21, 2017, 10:55 AM
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You need 2 byte RPM modifications, check out the link
https://www.evolutionm.net/forums/ec...te-thread.html
Old Mar 21, 2017, 11:12 AM
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Originally Posted by 01sporty
I think i just figured it out.........



the eval formula is 31.25*X=rpm
so if 8000 rpm and you solve for x than you get 256
now if you solve for x on the max i am seeing and its 7968.75 rpm that gives you 255
so I'm assuming we are using a raw value of 0-255 to log rpm and using the eval to convert it.

so I guess is there a different was of seeing more resolution or another request id that I can log to be able to log above the 7968.75rpm??
Correct! This is true because 1 byte = 8 bits. [(2^8) -1] = 255

255 is the largest byte sized data structure that can be stored in memory for that digital value.

When logging 2 byte using the same logic = 16 bits. [(2^16)-1] =65535

You would have to rev to 2,047,968 rpm's to upset that resolution now.


...or I could be wrong and everything I just said was a joke

-pal215
Old Mar 22, 2017, 08:34 AM
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Thanks guys! I knew it was something dumb.
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