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post #21 of 72 (permalink) Old 04-02-2005, 10:21 AM
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Originally Posted by rob13572468
seriously, though, i the pic shows that it is possile to not only read the data from the ecu but interrupt and send new data to the cluster as well. it should prove to have some interesting possibilites including being able to reprogram the cluster firmware to accept new input data such as oil pressure reading or even to adjust the speedo to display corrected (actual) speed.
That's awesome Rob.. I have so many questions.. So far, I've only been able to muck up the display without sending anything sensible. I suspected it's because my own packets, though CANBus legal, are mixed with the real messages from the ECU.. Are you intercepting the real messages and blocking them, or throwing yours in alongside somehow? Taking over the display for our own measurements/purposes is probably the #1 killer app.. hats off to you.

One thing I've been wondering.. when you have these high-speed stationary experiences, does your master odometer advance?

The thing that made me ask about the E-Brake light being CANbus instead of discrete is that I was able to get it to turn on & off by sending messages. I didn't understand enough about the formatting to make it predictable, but it looked like it was at least possible. Same for the "key reminder" beeper.

Then I broke my laptop, so now I live vicariously through your hacks.
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post #22 of 72 (permalink) Old 04-03-2005, 04:22 AM Thread Starter
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Quote:
Originally Posted by Ground Loop
That's awesome Rob.. I have so many questions.. So far, I've only been able to muck up the display without sending anything sensible. I suspected it's because my own packets, though CANBus legal, are mixed with the real messages from the ECU.. Are you intercepting the real messages and blocking them, or throwing yours in alongside somehow? Taking over the display for our own measurements/purposes is probably the #1 killer app.. hats off to you.
besides the stanbdard logging equipment i have quite a bit of equipment that i have had to custom develop along the way... one of those is a man-in-middle device that basically consists of a microcontroller with two CAN interfaces and a serial interface for control and data. i can stop a particular ID# from passing through and then inject my own. it works well for this type of testing but was actually created out of the need to monitor message origination in networks with lots of nodes and messages (like 40 nodes and 200+ messages/second. with it i can plug the device in between one node and the rest of the network and see what mesages are coming from that particular node (and send different ones).

there is a quick and dirty way to do the same thing with a regular logger on systems like the elise where the message bandwidth is low; you simply inject a new message with a much highr frequency; say 100x/sec as opposed to the ecu's 10x/sec. statistics will cause the higher frequency message to reach the cluster most of the time even though the other one is still continuously transmitting.

Quote:
Originally Posted by Ground Loop
One thing I've been wondering.. when you have these high-speed stationary experiences, does your master odometer advance?
surprisingly, that is exactly what i was expecting to happen... but it did not. the recently posted wiring for the elise shows no other connection to the odometer but the CAN which means that at 160mph, the odometer should have been flipping digits at the rate of roughly 1 miles every ~20 seconds, yet it did not. perhaps there is an interlock condition that i have not found yet or there is a discrete odometer "tick" wire coming from the ecu that is not reflected in the current wiring diagram. some more investigation is needed.

Quote:
Originally Posted by Ground Loop
The thing that made me ask about the E-Brake light being CANbus instead of discrete is that I was able to get it to turn on & off by sending messages. I didn't understand enough about the formatting to make it predictable, but it looked like it was at least possible. Same for the "key reminder" beeper.
all of these show discrete wire connections to turn them on/off in the wiring diagrams but again, they could be wrong. ill do some checking.
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post #23 of 72 (permalink) Old 04-03-2005, 05:58 PM
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Quote:
Originally Posted by rob13572468
besides the stanbdard logging equipment i have quite a bit of equipment that i have had to custom develop along the way... one of those is a man-in-middle device that basically consists of a microcontroller with two CAN interfaces and a serial interface for control and data. i can stop a particular ID# from passing through and then inject my own.


Perfect. You've inspired me to do likewise with two CANBus USB adapters, a laptop and software-in-the-middle.

CANoreo
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post #24 of 72 (permalink) Old 04-05-2005, 08:16 AM Thread Starter
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well, i have again checked some extended data logs and so far no data appears on the bus that would correspond to an odometer advance pulse. its quite interesting in that there are either some discrete wires carrying signals or the code is hidden in the regular data... same goes for the brake/key sense. its probably going to take some in-depth research into the cluster itself.

below are that latest screen captures of the logger; i added in some real-time gauges and set up the calibrations for speed and such. Also added direct logging of the actual integer speed/rpm/temp...

on a side note, i was reading thru the thread on the DL1 datalogger and i couldnt help but think how easily one could homebrew a unit that would have all of the same features plus lots of extras as well as the external sensors for alot less than the thousand bucks that the DL1 goes for... you would basically need two ADXL accelerometers at ~$5 each. The core processor would be a picmicro running at 40 mhz (which is actually faster than the DL1 at 24 mhz). you can now get the controllers with 40 and even 64 pin counts which would allow you to have 8- 12volt inputs, 8- analog inputs (0-5v), 8 analog (0-12v), and 8 frequency inputs. There would still be plenty of pins left for the GPS, CAN, 9141, and a serial/usb. A 5 hz gps board runs around $45 and the only other thing that you would need would be the flash card interface.

The total cost of parts would be somewhere around $110 for a unit that would be able to sample at up to 160 times/second at 32 bits (although i suppose thats overkill). when you consider that its really just datalogging, the software could be coded quite easily and made open source so that anyone could write additional modules. the hardest part would be making the printed circuit board to hold all of the components but that could even be sublet out to a manufacturer that specializes in small runs (10-1000).

oh well... one more project to add to my never ending list
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post #25 of 72 (permalink) Old 04-05-2005, 08:45 AM
 
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Rob, the hardware is easy and readily available for datalogging. I have some 100 dollar loggers that work just fine, and that was many years ago. That's not usually the issue. It's what to do with the data, how to easily pull useful information out of it. Without hassles. Accelerometers are not enough - they drift, you need GPS in conjunction if possible. And you have to reconcile the GPS with the accel data as both have issues. The true strength of the Race Technology bits - the analysis software. In the price range in question, they really stand out and have for years. The company listens to users and is now working on version 6 of the analysis program. Some of my suggestions will be incorporated. Same from other users. Many folks who use the DL1 also buy or make a plug for available OBD 2 data. In some cases you can get nothing useful from it at the moment, sometimes power, ground and RPM. It's not very hard to just throw in some analog wiring to get the show on the road. For example there is a Boxter plug for the DL1 produced by one of the Dl1 dealers.
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post #26 of 72 (permalink) Old 04-05-2005, 09:27 AM
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Rob is it possible there is a second bus with the odometer and ebrake info on it. Possibly the spedometer plugs directly into it? Just a thought.
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post #27 of 72 (permalink) Old 04-05-2005, 10:35 AM
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Quote:
Originally Posted by rob13572468
well, i have again checked some extended data logs and so far no data appears on the bus that would correspond to an odometer advance pulse. its quite interesting in that there are either some discrete wires carrying signals or the code is hidden in the regular data... same goes for the brake/key sense. its probably going to take some in-depth research into the cluster itself.
Indeed there seems to be an extra wire that is JUST for the odometer...

Any thoughts?
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post #28 of 72 (permalink) Old 04-05-2005, 04:05 PM
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FYI the ecu uses can 2.0b not 2.0
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post #29 of 72 (permalink) Old 04-06-2005, 02:31 AM Thread Starter
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Originally Posted by Stan
Rob, the hardware is easy and readily available for datalogging. I have some 100 dollar loggers that work just fine, and that was many years ago. That's not usually the issue. It's what to do with the data, how to easily pull useful information out of it. Without hassles. Accelerometers are not enough - they drift, you need GPS in conjunction if possible. And you have to reconcile the GPS with the accel data as both have issues. The true strength of the Race Technology bits - the analysis software. In the price range in question, they really stand out and have for years. The company listens to users and is now working on version 6 of the analysis program. Some of my suggestions will be incorporated. Same from other users. Many folks who use the DL1 also buy or make a plug for available OBD 2 data. In some cases you can get nothing useful from it at the moment, sometimes power, ground and RPM. It's not very hard to just throw in some analog wiring to get the show on the road. For example there is a Boxter plug for the DL1 produced by one of the Dl1 dealers.

i absolutely agree with you that the race technology product is excellent, but the idea is to take the best parts and implement them into a home built design. there is often a false notion that commercially developed is inherently better than home brew but that is not always the case. a good example of this is the megasquirt ecu which started out as an open source project to build an ECU, and now is full featured with support for just about any engine configuration possible, including ignition timing and emissions; it is actually better than many computers that come on production vehicles.

the idea is to build a better unit AND better analysis software using open source and community help and save some money in the process. it just takes a bit of effort and interest.
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post #30 of 72 (permalink) Old 04-06-2005, 02:53 AM Thread Starter
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Originally Posted by scottyb
Rob is it possible there is a second bus with the odometer and ebrake info on it. Possibly the spedometer plugs directly into it? Just a thought.
when i pulled the cluster before i did not notice any other data bus lines and at the time i didnt have the wiring diagrams to compare against and see if any additional or different wires were present. if i had to guess i would bet that the odometer advances using the speedometer data but also checks additional discrete inputs. that the wiring diagram does not reflect any of these inputs means that a direct comparison of the wiring will be needed to figure out how it works. thats next on the agenda...


BTW: if anyone has sheet 1 of the wiring diagrams (either the 111R or 111F) i would greatly appreciate if you could post it here. my goal is to publicly document the layout and function of the entire electrical system so that everyone in the community can have access to the information things like development, accessories, and repairs. for reference, sheet 1 has the starter button, supply points, ignition, etc. thanks in advance, i really appreciate it.

Last edited by rob13572468; 04-06-2005 at 03:14 AM.
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post #31 of 72 (permalink) Old 04-06-2005, 03:16 AM Thread Starter
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Quote:
Originally Posted by darkSol
Indeed there seems to be an extra wire that is JUST for the odometer...

Any thoughts?

no, the lead from A1 is the 12 volt supply lead for the odometer; no signals on it.
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post #32 of 72 (permalink) Old 04-06-2005, 03:32 AM Thread Starter
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Quote:
Originally Posted by charliex
FYI the ecu uses can 2.0b not 2.0

2.0b is the specification for 29 bit identifiers rather than 11 bit but is backward compatible. the identifier is more commonly known as the message ID and 2.0b was drafted because larger networks could concievably use more individual messages than the 2048 maximum. using 29 bit id's allows for over 500 million.

funny thing about the elise is that it still only uses 11 bit ID's even though it supports the 2.0b specification. future upgradeability i guess....
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post #33 of 72 (permalink) Old 04-06-2005, 05:09 AM
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Quote:
Originally Posted by rob13572468
the idea is to build a better unit AND better analysis software using open source and community help and save some money in the process. it just takes a bit of effort and interest.
If anyone is interested in this, PM me, and I could set up a mail-list. I'd be interested in getting something like this going. Not because I don't think the DL1 is a good product, but because I'm sick and would like to be able to program the firmware of one.

I've been thinking about this for a while, but have put it off. Now I'm starting a project at work that is going to be somewhat similar, so I'm thinking it might be a fun thing to try.
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post #34 of 72 (permalink) Old 04-06-2005, 09:34 AM
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2.0b, indeed rob its just nice to know you can use it if you needed, the toucan is a decent little system.
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post #35 of 72 (permalink) Old 04-06-2005, 06:42 PM
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Originally Posted by Evl
If anyone is interested in this, PM me, and I could set up a mail-list. I'd be interested in getting something like this going. Not because I don't think the DL1 is a good product, but because I'm sick and would like to be able to program the firmware of one.

I've been thinking about this for a while, but have put it off. Now I'm starting a project at work that is going to be somewhat similar, so I'm thinking it might be a fun thing to try.
I'm very interested in this. I like the idea of doing it myself even if it doesn't come out as well. I'm a software engineer by trade. I've been doing low level c programming recently. So, any gui's I write are text based, but that's the way I like it.
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post #36 of 72 (permalink) Old 04-11-2005, 11:42 PM
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Rob, do you think the speed byte might simply be kilometers-per-hour? It's lining up pretty close here. A full 0xFF km would be 159 mph, or full tilt.

Also, I'm thinking the 0x02 bit might be the oil pressure indicator in the status byte.

Not sure about the 0x04 bit. Mine stays set before and while cranking, and goes out after the car is running for only a second, and comes on again about two seconds after shutting down.
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post #37 of 72 (permalink) Old 04-12-2005, 10:14 AM
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I wonder if anyone will use this information for evil? Not me-my "doings" in the car have been recorded and shipped twice already.

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post #38 of 72 (permalink) Old 04-12-2005, 10:59 AM
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Quote:
Originally Posted by Ground Loop
Not sure about the 0x04 bit. Mine stays set before and while cranking, and goes out after the car is running for only a second, and comes on again about two seconds after shutting down.
That sounds like it could be an oil pressure signal. On means no pressure, off means pressure - like an idiot light. Does the signal match the oil warning light's activities?

Unfortunately it doesn't sound like it indicates the amount of oil pressure...




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post #39 of 72 (permalink) Old 04-12-2005, 04:02 PM
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I found a site that sells Lotus parts and saw that there is a speed sensor for Elises. It is for series 2, so I dont know if it applies to US cars, but it means that their might be a way to link into something for Los Angeles touring pack radios that have the adjustment for volume based on speed.

The link also lists other sensors too.

Lotus speed sensor

Last edited by xxxotic; 04-12-2005 at 04:04 PM.
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post #40 of 72 (permalink) Old 04-12-2005, 09:40 PM
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Originally Posted by xxxotic
I found a site that sells Lotus parts and saw that there is a speed sensor for Elises. It is for series 2, so I dont know if it applies to US cars, but it means that their might be a way to link into something for Los Angeles touring pack radios that have the adjustment for volume based on speed. [/URL]
Probably same sensor as the 111R/Fed-Elise uses on all 4 wheels for the ABS.

The 'normal' Elise (without ABS of course! ) uses one different bearing wich has the toothed ring for the speed sensor installed. The 111R/Fed-Elise uses 4 of those..

Perhaps a speed-pulse can be 'borrowed' from the ABS unit in the Fed-Elise.

Bye, Arno.
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