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Tim Hardisty

V88, CAN data for EGT, Ethanol and WG Duty

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I have a customer with a V88 and one of our Toucan displays and I'm trying to assist him in getting EGT and Wastegate duty displayed.

I've created him a custom ".lcc" file, which has all the generic dash, then with an additional frame containing AN6 (which his 0-5V EGT is connected to) and Wastegate duty. But, unlike in the later G4+ PCLink software, you cannot see or edit the parameter scaling.

Does anyone know how these two parameters - and Ethanol % and temp - are scaled? I've asked tech support and they don't know :o

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8 hours ago, Tim Hardisty said:

I've asked tech support and they don't know :o

Sorry Tim, I’m not sure how you got that answer but of course we will have that info.  I’m not at work now but will confirm later when I’m at work.  It should be the same as G4+

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2 minutes ago, Adamw said:

Sorry Tim, I’m not sure how you got that answer but of course we will have that info.  I’m not at work now but will confirm later when I’m at work.  It should be the same as G4+

I was a little surprised!  G4+ scaling doesn't seem to work, but could be an error on my part. If you can confirm that it really is the same, I'll sort it "my end"; if not, then the correct scaling info will obviously help :)

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Ok, I can confirm the scaling is the same as the G4+:

%Ethanol, 1:1, no scaling.  0%eth = 0CAN.  100%eth = 100CAN

WGate DC, 10X multiplier.  0%DC = 0CAN.  100%DC = 1000CAN

EGT, 50°C offset.  0°C = 50CAN.  500°C = 550CAN, 1000°C = 1050CAN

If your scaling looks ok then it could possibly be a frame layout issue, since that is not well documented for the V series.   If you wanted to attach your .lcc CAN stream I can run it in an ECU here with a stiffer connected so you can see how the message is laid out.

Im sure all parameters are always sent as 2 bytes with least significant first in the V series.

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Thanks Adam. I've attached the .lcc file. 

As far as EGT is concerned, there isn't an EGT parameter as such that I can see, so it is just AN6 (to which the 0-5V EGT amp is connected) that's in the stream. I've added it twice so the stream is near-enough identical to the .lcs file I'm evolving for G4 which has 2 EGT channels.

Toucan Enhanced Dash.lcc

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Just been trying my G4+ setup and the scaling of the EGT in the .lcc and .lcs files is probably wrong - I had it set for the Thunder's internal EGT amplifier which needed a different scaling. But WG Duty does work OK on the G4+. About to code in the ethanol stuff.

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Most useful - thank you Adam :D

As far as EGT is concerned, how is that configured for a V88 since there's no EGT parameter, per se, that I can find? I just to make sure there isn't another variable to take into account, such as the analogue input linearisation table?

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This is what I was using: K4qOLVL.png

So in your CAN template you just broadcast "AN V6"  The ECU sees that it is configured to temp units by a cal table and scales the CAN data appropriately.  I tried both a linear calibration and a non linear table and got the same result over CAN.

One catch to look out for is that last 0x0E frame gets shortened to 6 bytes, some devices might not interpret that correctly?

 

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I now have these parameters working correctly on a G4+, using the CAN data scaling of the V88 as above - again, many thanks.

I have done this by creating custom frames to add the new parameters in, but it's a bit messy for the end user so I thought I'd create a complete custom set of frames based on an existing .lcs file from this forum for the generic dash stream. This stream checks out with the built-in generic dash stream I've used for years.

But if I load the file in, PClink complains that there are "too many parameters in Streams". It will only work if I reduce the number of frames from 13 down to 11 (so from 39 actual parameters down to 33).

Why is that, since the built-in 13-frame stream obviously works?

I can probably work around it, but it would be good to know why!

 

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Been pondering this, and think the 50 parameter limit must include the sequential ID word itself...so only 12 frames allowed in theory (48 parameters/IDs). Although had to trim it 11 before it was accepted (44 parameters/IDs), so may not be the correct explanation (no other streams active).

There's also an implication that a built-in stream is not limited to 50 parameters?

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Im not sure on this, I dont ever remember needing to send that many parameters from the ECU, although I do understand what you are trying to do.  I could reproduce it here but I got up to 14 frames and 43 parameters before I got that message. 

I have put the question to engineering to see what they come back with.  

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Just found that even if the streams are set to OFF in the "MODE" tab, any frames actually defined in those unused streams do count towards the 50 (or whatever the limit is) and cause the "error".

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Hi Tim,

The limitation apparently is the amount of memory that is allocated to that function and it is not easy to adjust that allocation without upsetting other stuff...  Both the number of frames and number of parameters will eat up that allowance, so the limitation is a bit of a moving target. 

I wa thinking since our "Generic Dash" stream has quite a bit of "junk" (or not so commonly used parameters) I wonder if it might be a better option going forward to use say the "Dash2Pro" stream as the base to build from, as it has most common parameters and less crap.  It uses 3 sequential ID's so you could just add anything extra on the end using a new ID. 

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Thanks Adam. There are around 30 parameters I want, so I'm now building my own sequential stream and eliminating the "junk" as you suggest. I was trying to retain backwards compatibility so existing users weren't forced into having to update their map, just to get some new functionality, so I won't be able to achieve that . No biggy.

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