EE dissection

[kur4o]

It will be really hard because map scalars are everywhere, and if you plug 3 bar map ad voltage at 100kpa will be 1/3 of 5v I guess which will be 1.67 volts and from 0 to 1.67 you get very low resolution, unless you drive boost or near boost all the time, reolution will suffer.
Much easier will be to add second 2 or 3 bar map sensor on one of the free ad channels, make new 3d table with bpw adder or whatever you like. That way you won`t lose resolution off boost and can get full control on extra fuel needed. Also you can map spark retarder that use the second map sensor.
Of course we will need full graph with AD counts vs boost on the new map sensor so it can be dialed in proper way and a volunteer with engine to sacrifice, Initial test may be done with variable potentiometer hooked on the ad channel on NA engine

[steveo]

imo, that sounds like a really complicated project without a huge amount of real-world gain for tuning boost

since full resolution in 5 map steps is totally unnecessary for a boosted engine, hell, even an n/a engine would get by on 10 map steps, and tripling table sizes would require a few thousand bytes...

why don't we work on adding 8 columns of MAP, making 24 map column spark and VE tables?

that'll give you a bit more resolution to play with in boost, with a 2 bar, you'd get 12 columns in boost, 12 columns out of boost. isn't too shabby, compared to the 8 you get now..

i'd be willing to make a second EEX XDF just for boost so it would be usable..

[fbody_Brian]

So I got around to testing that pe spark adder. It's set at 5 be default. I had timing set to max at 33° wot, and was seeing 38° in my logs. After setting it to 0, I'm now seeing 33° as I would have expected. So put me down as one more person who has got rid of the mysterious added PE timing by changing this parameter.

[steveo]

i'd love to know how it works. a pe spark adder is nice. we should use it properly instead of nerfing it

[Terminal_Crazy]

So I got around to testing that pe spark adder. It's set at 5 be default. I had timing set to max at 33° wot, and was seeing 38° in my logs. After setting it to 0, I'm now seeing 33° as I would have expected. So put me down as one more person who has got rid of the mysterious added PE timing by changing this parameter.

Where is that stored ? I couldn't see any reference to it in the xdf file.

Mitch

[Terminal_Crazy]

Has anyone got any info/writeups on the knock sensor circuit code ?

This might actually be better in a different thread.

I've been suffering from knock for a while with my motor. I'm 99.9% certain it's false but couldn't find much info on handling it.
Anyways.
I spent yesterday researching what i could find out re desensitizing it.
Trawling the web did'nt reveal much evidence other than delete it or switch it off.
I eventually found an image of a circuit to mod the signal from PCM to knock sensor using a couple of resistors, "The Knock Knocker" by Mike Chaney.

Today I've been playing with an adjustable version & recorded some results which look promising.
I can variably reduce the knock counts from ~500 down to ~60 every time i tap the alternatorby adjusting the pot.

I've no evidence yet & further things to investigate but presume I'm cutting the signal off earlier by reducing this level.
I'll post results some time soon.


What actually prompted me to post though was that i couldn't recall seeing anywhere the knock counts were referenced.
I then wondered what the PCM's strategy was as to using the Low Octane Table.
I can see 3 x vs Knock sensor voltages listed but no other references.



Cheers
Mitch

[fbody_Brian]

i'd love to know how it works. a pe spark adder is nice. we should use it properly instead of nerfing it

I agree!, but for the moment it's nice to be able to just zero it out so I know that the timing is what I expect it to be.

Where is that stored ? I couldn't see any reference to it in the xdf file.

Mitch

I'll have to look later, think it's in misc, or experimental. Don't have access to the computer right now.

[steveo]

Has anyone got any info/writeups on the knock sensor circuit code ?

This might actually be better in a different thread.

I've been suffering from knock for a while with my motor. I'm 99.9% certain it's false but couldn't find much info on handling it.
Anyways.
I spent yesterday researching what i could find out re desensitizing it.
Trawling the web did'nt reveal much evidence other than delete it or switch it off.
I eventually found an image of a circuit to mod the signal from PCM to knock sensor using a couple of resistors, "The Knock Knocker" by Mike Chaney.

Today I've been playing with an adjustable version & recorded some results which look promising.
I can variably reduce the knock counts from ~500 down to ~60 every time i tap the alternatorby adjusting the pot.

I've no evidence yet & further things to investigate but presume I'm cutting the signal off earlier by reducing this level.
I'll post results some time soon.


What actually prompted me to post though was that i couldn't recall seeing anywhere the knock counts were referenced.
I then wondered what the PCM's strategy was as to using the Low Octane Table.
I can see 3 x vs Knock sensor voltages listed but no other references.



Cheers
Mitch

there's no real knock sensor circuit code that deals with the analog side, the knock module does all that in hardware, then just sends a 'knock' signal on or off to the ecm and the ecm increments the knock counter.

i usually just nerf the stupid knock sensor in the range it's giving me trouble. a conservative timing table with a conservative AFR doesn't really need a knock sensor anyway.

reducing the effective number of knock counts per event may not give you great results, it will probably just slow the attack rate, which you can do in software.

[steveo]

Where is that stored ? I couldn't see any reference to it in the xdf file.

Mitch

experimental > unknown spark adder
(in the latest version)

stock is 5, affects PE only, reccommend 0

[steveo]

i looked at the code and it definitely looks like it's in power enrichment and per rpm but i can't really figure how it scales. maybe kur4o has looked into it a bit more.

[Terminal_Crazy]

there's no real knock sensor circuit code that deals with the analog side, the knock module does all that in hardware, then just sends a 'knock' signal on or off to the ecm and the ecm increments the knock counter.

reducing the effective number of knock counts per event may not give you great results, it will probably just slow the attack rate, which you can do in software.

After having another play today with the PCM settings I think the overall effect is similar but the PCM has finer control across the range.
I now understand it better.

Thanks.
Mitch

[kur4o]

Actually the spark adder is double word value. Stock value is $0510.
It is not PE related. It is always applied. I guess it is scaled vs low refence pulse word_a1.
I need to get some logging of a1 values to fully understand how it is used.

From my observation the spark adder is step added with increasing rpm up to 5 degrees on stock log file.[$0510 value][Can someone confirm changing 05 to 02 results only 2 degree SA spread]. It is more obvious in full throttle because you have fixed SA to compare, but my assumption is it is added all the time if conditions met.
The main reason for this could be SA compensation for optical sensor signal deviations at higher rpm.

[steveo]

16 bits is a hell of a range for a spark adder. i wonder why they did that.

my assumption is it is added all the time if conditions met.

those conditions are what we need to look into

5F93	15 34 08        @134	bclr	l_0034_tts_1, #%00001000
5F96	57              @135	asrB	
5F97	F7 01 4A        	staB	L014A
5F9A	DE A1           	ldX	l_00a1_ref_period_12x
5F9C	FC 20 46        	ldD	L2046                             ; $0510 (1296)
5F9F	02              	idiv	                                  ; integer 1296/00a1 -> X
5FA0	8F              	xgDX	                                  ; -> D
5FA1	04              	lsrD	                                  ; / 2
5FA2	C9 00           	adcB	#$00
5FA4	F7 01 4C        	staB	L014C
5FA7	F6 01 4A        	ldaB	L014A
5FAA	FB 01 4C        	addB	L014C
5FAD	F7 01 49        	staB	l_0149_tts_GP6ESPKO
5FB0	12 01 20 22     	brset	L0001, #%00100000, @138
5FB4	86 5A           	ldaA	#$5A
5FB6	10              	sBA	
5FB7	16              	tAB	
5FB8	B6 15 F6        	ldaA	L15F6
5FBB	01              	nop	
5FBC	FE 15 F6        	ldX	L15F6
5FBF	3A              	aBX	
5FC0	FF 14 54        	stX	L1454
5FC3	12 23 80 04     	brset	L0023, #%10000000, @136
5FC7	86 03           	ldaA	#$03
5FC9	20 02           	jr	@137

[jthompson122183]

ive asked around in several places and found that the 2046 double byte on eside is "est system lag time"
This is what i got from tc when asked:

"Hi Jonathon,

This is the EST system time lag and is meant to correct for the latency in the spark system. It is a fixed value in usec:

lag (usec.) = N x 0.08477

Of course since the time lag is a fix time value the correction in terms of degrees will depend on RPM.

Best regards,
TC
"

[jthompson122183]

i was curious about the 21cd table on the tside and got the first pic as a response
i'm interested in the three bytes before each one of these tables shown in the second and third pic, there is 4 tables in this area also.
Are these the points in which the pcm can say the o2 sensor can swing back the other direction "Flyback Voltage" like the 4th picture
the first of the three bytes has something to do with tps, is this min or max tps that the pcm uses to determine when to use the next two bytes?




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