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I've seen and used many OBD, GPS and professional data loggers on the market. There's one things missing.... a cheap data logger that's easy to use and has software that provides good information for track use and coaching. Look at the OBD market alone, there's tons of companies producing cheap products, but none of them are really great.

With people on this board interested in making one, who is going to produce something for all of us to use?

My only issue with doing all this freeware stuff... those who program it will find other interested and stop development. So maybe a community project should be setup so that new people can continue where others left off?
 

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Fast, cheap , good you only get two.

I have my own OBD II logger, but there are a few problems, namely the update rate is so slow that it doesn't really seem worthwhile, you really need to add external sensors or tap into the existing sensors.

A couple of people have talked about making a free one, why not go ahead and start one and see who joins in.
 

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charliex said:
Fast, cheap , good you only get two.
And you usually don't even get two...;) rotfl
 

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Does the Lotus ECU implementation of CANbus implement a CAN Application Layer like CANopen, or is it a proprietary protocol? I'm looking at the OSI diagram on this page:

CAN Application Layers

If I buy a CANbus->USB connector and want to write some custom software can I get raw access to the data stream without using proprietary driver API? From reading through various posts it seems as if others have been parsing the raw packets.
 

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Discussion Starter #67
Does the Lotus ECU implementation of CANbus implement a CAN Application Layer like CANopen, or is it a proprietary protocol? I'm looking at the OSI diagram on this page:

CAN Application Layers

If I buy a CANbus->USB connector and want to write some custom software can I get raw access to the data stream without using proprietary driver API? From reading through various posts it seems as if others have been parsing the raw packets.
go back to the beginning of this thread and read the first page: There is no application layer at all: Its literally just one message with all of the speedo data stuffed into the 8 bytes. I guess you could say its proprietary but its so simple that it doesnt really matter: just one frame sent from the ECU to the cluster.

I do alot of mercedes CAN work and by comparison you will see an application layer used on each of the *six* seperate CAN networks that are built into the newer models. In fact there is a seperate application layer actually exists across all of the networks since they are interconnected via gateway translators that relay specific messages from one network to the next. The mercedes application layer is proprietary as are most automaker vehicle networks; they arent really interested in open networks. The only exception is MOST fiber networks which uses common standards but even then non of the manufacturers adhere to the standards enough to make components interchangeable.

As far as using a USB adapter to access the CAN data you dont need to even worry about any sort of API except for the CAN adapter itself (e.g. to handle the actual data transfer over USB). most USB-CAN adapters have their own API and software examples so that you can write your own code; PCAN-USB by PEAK is a good example. As far as the data itself you get back 8 bytes and then just parse it.
 

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purveyor of lightness
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I love annual post resurrections ;)

Rob you wouldn't happen to have a little black box that would take the following inputs and drive the stock cluster would you?

- rpm (via a low voltage coil line) also trips shift light when required (adjustable)
- speed (via stock wheelspeed sensor tap)
- temp (via stock sensor tap)
- fuel level (via stock sensor tap)
- oil pressure light (via stock sensor tap)
- miscellaneous input for mil light

I just remembered that you were working on this and wondered if anything had progressed further as mentioned in this post...

http://www.lotustalk.com/forums/894574-post4.html

Thanks!
 

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i've been using this thread to work on my own ECU to lotus dash conversion box - i'm running a standalone ECU - thought some might be able to use what additional info i found.

working on the awesome work of the OP, Rob, above ....

frame data: aa bb cc dd ee ff gg hh

aa = dash understands speed in kilometers per hour (good as i live in Australia and we are metric)

bb = unused

cc = first part of rpm. take rpm from ecu output eg. 4000rpm and divide by 256 = 15 (dont care about the decimal left overs(.625)) now convert 15 to hex (0F) and send to the dash.

dd = second part of rpm. take the second two digits of rpm eg 4090, now just use 90 and convert to hex (5A) and send to the dash.

ee = fuel - all depends on your ECU calibration. as Rob states - 00 - FF

ff = engine temp. dash needs to understand engine temp in deg F for some reason. and has an offset of -14. so for 90 deg C engine temp use the following: ((tempin * 9.0 / 5.0)+32)+14 where tempin variable is 90

gg = various dash lights:
send the following to the dash - all in hex. tc = traction control light.
00 = off. 01 = shift light. 02 = MIL. 03 = Mil&Shift. 04 = oil. 05 = oil&shift.
06 = oil&mil. 07 = oil&mil&shift. 08 = tc. 09 = tc&shift. 0a = tc&mil.
0b = tc&mil&shift. 0c = tc&oil. 0d = tc&oil&shift. 0e = tc&oil&mil.
0f = tc&oil&mil&shift

hh = unused by dash.

Hope this helps some people, i spent a while working it out as i dont have lotus ecu connected up any more - just a dash on my workbench with a couple of arduino boards - 1 sending CAN and one listening and resending to dash. my ecu outputs CANBUS, but it is not able to modify the values....
 

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Digging into the past; but has any hardware s/w come of this for us not programming geeks? Wanting to dump info to datalogger and Valentine 1 display to dash. Also where does steering angle and TPS and MAF data go onto CAN bus of newer cars? FYI, the speed conversion of x*o.68 = mph works out to be the conversion factor from feet/sec to miles/hr 60*60/5280= 0.681818 Also any knowledge as the CANbus protocol used in the Evora?
 

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Thanks for your hard work rob13572468 and Tang0_au. I'm running a Haltech Elite and am working on converting its CAN output to something the Lotus dash can understand. Thanks to your efforts I've gotten to the point where I'm doing 100km/h in my garage with the handbrake on.
 

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I've finished the Arduino software to convert Haltech CAN output to something the Lotus dash can understand. Works pretty well, complete with gauge sweep, but the fuel gauge goes up veeeeery slowly. Not sure what is wrong with that yet.

Source code is available here for those interested: https://github.com/dineshpannu/CANBusTriple-Lotus/

With most of the interesting stuff in:
https://github.com/dineshpannu/CANBusTriple-Lotus/blob/master/avr/examples/CANBusTriple_Lotus/Haltech.h
https://github.com/dineshpannu/CANBusTriple-Lotus/blob/master/avr/examples/CANBusTriple_Lotus/LotusDash.h

The Arduino unit I'm using is this: https://canb.us/
 
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