aidandj

iTrader: (5)

Another update. I've been wanting to have a knock warning on the racepak. But the only signal I could find was knock in. Which is in %. And that varies depending on RPM. Then Brain pointed me to the ECU Status bitfields. So I can transmit status7, and if it equals 16 then we have knock indicated.





Here is the racepak setup. When knock is detected the output will be 16. So setup your warning so that it warns when it equals 16.

amaff

Thank you so, SOO much! The IQ3 manual was practically useless, and the MS documentation was missing a whole host of implied knowledge. I was completely wrapped around the axle trying to get this thing to play nice and most of the data fields you need to enter are completely undefined (and are different between the MS documentation and the RacePak software).

If we ever find ourselves sharing the same piece of asphalt, I owe you several beers. You're a legend.

Question, did you have any issues with the Ethanol content display? I'm running basic E10 pump fuel for now. TunerStudio shows right at 10.x%, but the IQ3 is seemingly a random number generator, occasionally showing up to 110%, which, obviously, is impossible, so something else is up.

Lokiel

Just a minor correction to aidandj's initial comments:

"Then Brain pointed me to the ECU Status bitfields. So I can transmit status7, and if it equals 16 then we have knock indicated."
and
"When knock is detected the output will be 16. So setup your warning so that it warns when it equals 16."

Knock is actually detected when the value of field "Status 7" ANDed with the value 16 equals 16.

Some background (for non-programmers):

On the MS, when knock is detected, Bit 4 of the Status 7 field is set, as shown in the tables provided by aidandj.
Bits are identified starting at zero, not one.
This is where the value "16" comes from (ie. 2^4 = 16)

The overall value of the Status 7 field is based on all bits set in the field and the bits in these fields are NOT mutually exclusive (ie. the Check Engine and A/C On bits can both be set at the same time).
eg.
If the only bit set is Bit 4 (knock bit), the value is 2^4=16.
If the A/C is on (Bit 5) , and knock is detected (Bit 4), these bits are set so the Status 7 value is 2^5 + 2^4 = 32 + 16 = 48.
If Check Engline is on (Bit 6) , and knock is detected (Bit 4), these bits are set so the Status 7 value is 2^6 + 2^4 = 64 + 16 = 80.

If you logically AND the value of field Status 7 with the value 16 and the result is 16, you know that knock has been detected.

I don't have a Racepak dash to determine how to implement this "field Status 7 AND 16" calculation but if you can you should do it, or be aware that it's NOT just the value 16 that you should be looking for to observe knock detection, any value where Bit 4 is set indicates knock.

aidandj

iTrader: (5)

Welcome! Glad I could help. I only had the problem with "noisy" signals, which I commented on a few posts up. 2.13 was the only firmware that worked for me.

amaff

Ah that's right. I'll see if I can't find somewhere to pull that firmware down and give that a go. Thanks again!

amaff

Well, I got 2.13 on and that went fine for the most part (other than partially bricking the dash until I re-wrote out all the VNET channels to it. It seemed VERY confused).
However, now I can't get the "and" warnings to work. IE: Oil pressure <20 AND ECU RPM > 400, for example. It basically gives me a warning 100% of the time. Not really sure what to make of that. Curious if you had an issue. I did check the channel through 1 of the display screens and it's giving good data (as is the Ethanol% now, thank you very much! ), but for some reason the dash just can't seem to parse the "AND" warnings.
Any thoughts?


EDIT: Figured out the oil pressure warning issue I was having. For some reason (pretty sure I can see it clearly in the mirror...), different Display Pages had different minimum values for the RPM graph, and that was, for reasons I can't begin to fathom, screwing up how the "warnings" section was reading the RPM numbers.
What I wanted (and now have) is oil pressure to only warn if RPM is >400 and <9000 (ie: only warn if the engine is running), and it would warn constantly running or not, even with good pressure. Once I made the min-values consistent between the RPM graph for all 4 display pages, it worked.
I have no clue why, but I'll take the W.
Now to figure out how to get my "2-step active" warning to work...

amaff

Were you able to get the status bitfields to display? I'd like to warn when Launch control is active, but I'm struggling with what to set the warning limits to to make it work.

Raymond_B

Aidan, I signed up here to say a big thank you for this post. I do not have a Miata, but I am running a RacePak with an MS3/3X v3.57 and was really disappointed with it until I came here and read your post. Even with 3.14 F/W I was having issues with the dash and was ready to sell it. Once I read through this guide it helped immensely with some of the settings that are completely missing from any RacePak or Megasquirt docs. Now I just need to figure out why my temp reading goes to 0 and then back to normal every so often. Other than that all is good! Thank you again.


-Raymond

aidandj

iTrader: (5)

Glad I could help.