How does the Evo ECUs do ignition advance interpolations?
and fuel map interpolation?

has someone pulled the code to get the calculations?

I found this:
http://en.wikipedia.org/wiki/Bilinear_interpolation

I want to calculate what the ECU Target Timing is at each RPM/LOAD based on interpolation, is there any point? because I think this is what AFRMAP already is? someone correct me if I'm wrong.

is there any target timing advance? or is it what is logged is already the target timing advance based from current rpm/load on the timing map?

 

The interpolation is the same as for AFR, all 3D maps are interpolated same way, sub_B16 does the job. I have not deciphered the subroutine but it is deciphered by mrfred as

((255-r6)*r5 + r6*r4)/255 -> r0

So it seems, its more of trilinear interpolation, assuming both octane maps are in concern and octane number is a weight factor.
http://en.wikipedia.org/wiki/Trilinear_interpolation

what is logged is already the target timing advance, but some corrections take place after/before interpolation like knock correction, lean spool etc.

ROM:00000B16
ROM:00000B16 ; =============== S U B R O U T I N E =======================================
ROM:00000B16
ROM:00000B16 ; Attributes: noreturn
ROM:00000B16
ROM:00000B16 Interpolate_3D_Map: ; CODE XREF: sub_105BE+1A6p
ROM:00000B16 ; sub_141C8+7Ap ...
ROM:00000B16 mov.l r10, @-r15
ROM:00000B18 extu.w r4, r4
ROM:00000B1A extu.w r5, r5
ROM:00000B1C extu.w r6, r6
ROM:00000B1E mov.l @(h'100,pc), r10 ; [00000C20] = h'FF
ROM:00000B20 cmp/hi r10, r6
ROM:00000B22 bf loc_B26
ROM:00000B24 mov r10, r6
ROM:00000B26
ROM:00000B26 loc_B26: ; CODE XREF: Interpolate_3D_Map+Cj
ROM:00000B26 mov r10, r0
ROM:00000B28 sub r6, r0
ROM:00000B2A mulu r5, r0
ROM:00000B2C sts macl, r0
ROM:00000B2E mulu r4, r6
ROM:00000B30 sts macl, r4
ROM:00000B32 add r4, r0
ROM:00000B34 shll16 r10
ROM:00000B36 cmp/hs r10, r0
ROM:00000B38 bf loc_B3E
ROM:00000B3A bra loc_B64
ROM:00000B3C mov.l @(h'C0,pc), r0 ; loc_C00
ROM:00000B3E ; ---------------------------------------------------------------------------
ROM:00000B3E
ROM:00000B3E loc_B3E: ; CODE XREF: Interpolate_3D_Map+22j
ROM:00000B3E div0u
ROM:00000B40 div1 r10, r0
ROM:00000B42 div1 r10, r0
ROM:00000B44 div1 r10, r0
ROM:00000B46 div1 r10, r0
ROM:00000B48 div1 r10, r0
ROM:00000B4A div1 r10, r0
ROM:00000B4C div1 r10, r0
ROM:00000B4E div1 r10, r0
ROM:00000B50 div1 r10, r0
ROM:00000B52 div1 r10, r0
ROM:00000B54 div1 r10, r0
ROM:00000B56 div1 r10, r0
ROM:00000B58 div1 r10, r0
ROM:00000B5A div1 r10, r0
ROM:00000B5C div1 r10, r0
ROM:00000B5E div1 r10, r0
ROM:00000B60 rotcl r0
ROM:00000B62 extu.w r0, r0
ROM:00000B64
ROM:00000B64 loc_B64: ; CODE XREF: Interpolate_3D_Map+24j
ROM:00000B64 rts
ROM:00000B66 mov.l @r15+, r10
ROM:00000B66 ; End of function Interpolate_3D_Map

 

thanks, what does r6 r5 r4 r0 refer to?

 

not everyone logs the Octane field so if its not logged I will assume octane 100 when interpolating in the MapTracer.

 

will 2.7 fix the issue of vista 64 bit logging zeroes with 2.5?

 

((255-r6)*r5 + r6*r4)/255 -> r0 is the routine that does the linear interpolation between high octane and low octane maps. I haven't gone throught the table value interpolation routine yet.

 

I could not write it in plain text, thus the picture

 

awesome work acamus, thanks.

 

Will you include me into beta test team?
Or do I have to evaluate EvoScan with 1 bit modification?

 

... and some informations how to initialize logging of ACD/AYC.

 

Sure thing, do you have msn messenger?

Hopefully I will have the interpolation finished this week. I like to know how far off the ecu is when trying to match my target map. the ecu map is good, but it just doesn't show all the in-between values that you are always looking for.

 

I think its ok on evo7-9 logging because you can use AFRMap and TimingAdv to see the targets as per the ecu, but I know some model vehicles don't provide this.

 

evo4mad, how are you initilizing the logging of ACD? I ask this because it may help others determine how to read the ROM in the ACD controller. This thread discusses the topic :https://www.evolutionm.net/forums/sh...49#post6224149