ignition timing trims
Dec 15, 2008, 04:36 PM
#31
They are the same maps from what I can see, but change the address to 4c9d and the map will be correct. It is the same as for any of the other 3D ignition maps. Go back one number in any of your 3D timing tables and you will see the same thing. The same map is in my rom but it is zeroed by dafault, and also has an 11 as the first number. Not only that, but you are missing the last digit of your map :-)
Dec 15, 2008, 10:23 PM
#32
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See... not as silly as I look :-) Almost all of the 3D maps begin on an odd (not even) address, which I always thought was unique.
MrFred, if you want to see the map in my rom it is at 562d. It may be interesting because it is there but appears to not be called so you may be able to filter out code that is important or not for your own rom more quickly. On most roms this map is addressed just before the Stationary Thermo Fan maps so it is easy to find.
I have a quick question a little off topic: Is there a way in IDA to label or rename RAM addresses?
MrFred, if you want to see the map in my rom it is at 562d. It may be interesting because it is there but appears to not be called so you may be able to filter out code that is important or not for your own rom more quickly. On most roms this map is addressed just before the Stationary Thermo Fan maps so it is easy to find.
I have a quick question a little off topic: Is there a way in IDA to label or rename RAM addresses?
Dec 15, 2008, 10:28 PM
#33
there are 2 types of 3d/2d maps.
word length and byte length.
byte length maps start on an odd address, word on an even.
However you are correct, the vast majority of 3d maps are byte length.
Just press "n" to name anything. I presume you have already created a RAM segment Matt?
word length and byte length.
byte length maps start on an odd address, word on an even.
However you are correct, the vast majority of 3d maps are byte length.
Just press "n" to name anything. I presume you have already created a RAM segment Matt?
Dec 15, 2008, 11:06 PM
#34
...
MrFred, if you want to see the map in my rom it is at 562d. It may be interesting because it is there but appears to not be called so you may be able to filter out code that is important or not for your own rom more quickly. On most roms this map is addressed just before the Stationary Thermo Fan maps so it is easy to find.
...
MrFred, if you want to see the map in my rom it is at 562d. It may be interesting because it is there but appears to not be called so you may be able to filter out code that is important or not for your own rom more quickly. On most roms this map is addressed just before the Stationary Thermo Fan maps so it is easy to find.
...
Dec 16, 2008, 12:44 AM
#35
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Tephra, I am fairly certain I have the RAM segment setup when I first started, and I have been using 'N' to rename Unknowns but it wont let me do the RAM's. I might have to do some more playing around, I just thought there was another command I was missing. If I haven't is there a way to do it now?
Dec 16, 2008, 10:53 PM
#37
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I have a bit of an update for the idle stability timing control. I found what two of the 1D points do. For my rom, the 1D that Mr Fred referred to on the first page is at 174e (default = 128) is the sensitivity. Lower it and it responds slower, raise it and it is faster. The next address along at 1750 (default = 8) is the maximum possible timing adjustment. By default a max of 8 degrees can be added or subtracted by the control system. I tested these around an hour ago. Change 1750 to 1 and you only see 1 degree of timing shift, 2 gives 2 degrees, etc.... I also dropped the sensitivity to 32 and it almost stops. Tried a few between that and 255 and it started to respond much faster.
So, if for some reason you want to disable this feature you can quite easily just set either the sensitivity to zero or the max timing adjust.
Tephra, you may have found the bit control for this earlier in the thread. You mention one of the bits turns off low rpm timing?
So, if for some reason you want to disable this feature you can quite easily just set either the sensitivity to zero or the max timing adjust.
Tephra, you may have found the bit control for this earlier in the thread. You mention one of the bits turns off low rpm timing?
Dec 16, 2008, 11:20 PM
#39
Yep, that fits with my disassembly. The general formula to calculate the timing adjustment is:
DeltaTiming = x/64*(0.48*TargetIdle - 0.256*CurrentEngineSpeed).
or
DeltaTiming = x/64*(0.256*SnapShotEngineSpeed - 0.256*CurrentEngineSpeed)
x = the first 1D value that you mentioned.
For my Evo 9, the max timing adjustment range is only +/- 3 deg.
Do you think there is any value to tweaking these parameters? If yes, then I'll put these in the next ECUFlash xml series.
EDIT: I have not yet seen any periphery bits or other things that allow disabling any of the timing trim adjustment routines.
DeltaTiming = x/64*(0.48*TargetIdle - 0.256*CurrentEngineSpeed).
or
DeltaTiming = x/64*(0.256*SnapShotEngineSpeed - 0.256*CurrentEngineSpeed)
x = the first 1D value that you mentioned.
For my Evo 9, the max timing adjustment range is only +/- 3 deg.
Do you think there is any value to tweaking these parameters? If yes, then I'll put these in the next ECUFlash xml series.
EDIT: I have not yet seen any periphery bits or other things that allow disabling any of the timing trim adjustment routines.
Last edited by mrfred; Dec 16, 2008 at 11:23 PM.
Dec 17, 2008, 12:47 AM
#40
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In practice it is a powerful function for keeping idle stable without relying on the stepper motor to do all the work. Because the stepper moves in increments, much finer idle control can be done with the timing. I would say that the larger the cams are you are running, the more range you should give this control. The same goes for lower compression ratios, as it will need more timing to have an effect. I rarely see my car use more than 3 degrees even though it is set to 8, but it doesnt hurt to give it more range to do what it needs to do.
I would say to keep the function and list it in the next XML update. Alot of people would not know what to do with it, so I would rate it as an Advanced function left for the tuners. So for now those that want to disable it need to just set the adjustment limit to zero.
Tephra, I have seen the effect you are talking about while map searching. Something advances timing at very light throttle but I could not narrow down the conditions when it happens. It will do it at steady throttle and didn't seem to be accel related. This was tested with a flat timing map, no EGR timing, etc... and was very obvious.
I would say to keep the function and list it in the next XML update. Alot of people would not know what to do with it, so I would rate it as an Advanced function left for the tuners. So for now those that want to disable it need to just set the adjustment limit to zero.
Tephra, I have seen the effect you are talking about while map searching. Something advances timing at very light throttle but I could not narrow down the conditions when it happens. It will do it at steady throttle and didn't seem to be accel related. This was tested with a flat timing map, no EGR timing, etc... and was very obvious.
Dec 17, 2008, 01:34 AM
#41
Code:
<table name="Min Load for IAT-Compensated Ignition Trim" category="Timing" address="3ca8" type="2D" level="1" scaling="Load8"> <table name="Engine Speed" address="6b7a" type="Y Axis" elements="10" scaling="RPM"/> </table> <table name="IAT-Compensated Ignition Trim" category="Timing" address="3c8e" type="2D" level="1" scaling="TimingTrim8"> <table name="MAF Air Temp" address="714a" type="Y Axis" elements="8" scaling="Temp"/> </table>
Dec 17, 2008, 07:25 AM
#45
In practice it is a powerful function for keeping idle stable without relying on the stepper motor to do all the work. Because the stepper moves in increments, much finer idle control can be done with the timing. I would say that the larger the cams are you are running, the more range you should give this control. The same goes for lower compression ratios, as it will need more timing to have an effect. I rarely see my car use more than 3 degrees even though it is set to 8, but it doesnt hurt to give it more range to do what it needs to do.
I would say to keep the function and list it in the next XML update. Alot of people would not know what to do with it, so I would rate it as an Advanced function left for the tuners. So for now those that want to disable it need to just set the adjustment limit to zero.
...
I would say to keep the function and list it in the next XML update. Alot of people would not know what to do with it, so I would rate it as an Advanced function left for the tuners. So for now those that want to disable it need to just set the adjustment limit to zero.
...