Introducing ElanLogger

[tigerdog]

Brilliant bit of kit! It's wonderful to see someone with the "Newbie" label by their name, immediately contributing such a cool project. Kudos for upholding the longstanding tradition of innovative engineering that brought me to LEC, oh so many years ago.

[matts1972]

Just edited and replaced the Arduino software in my original posting with version 1.1
This adds some visual indication by flashing the builtin LED of the Arduino board in one second intervals after the log file has successfully been written and closed.
Errors will flash quickly 5 times per second instead.
So while you are driving and nothing is flashing you can feel reassured that ElanLogger is still happily logging.
Cheers
Matthias

PS: to see the LED in Ken's ElanLogger box you will have to drill a hole in it.

[lotusrepair]

Has anyone offered to produce and sell these? I would buy one.

[matts1972]

It is really an easy project to build one. An oil change on our cars is more challenging (at least for me ). But of course, you have to invest a few hours to get the parts and put everything together. Also, while I love Ken's 3d printed box, it is rather costly (especially if you do not have a printer). So to build solid ElanLoggers in mass production, a few challenges remain.

[CalElan]

this is brilliant -- I have a ton of portable apple devices, but my one PC is a HUGE tower sat in the office.. this solves my problem...
Thanks Guys!

[HJ2]

Finally a valid reason to buy me an Arduino board
Super gemacht, vielen dank!

Let's order parts now.
Thanks for the housing as well Ken!

[matts1972]

Would love to hear from you when you built one and how it worked out.
This will hopefully encourage more members to go for it.
Thanks for all your feedback so far.

[HJ2]

Will do
I hope this will go faster than BCN's shift cable review

Edit:
Parts are now ordered, I hope that any P3 will do (as I ordered somewhere else, and that I not run into software problems!
This will be my first raspberry experience, and I am not afraid of hardware, but software....
This will be a painfull but educational experience i guess

[matts1972]

Parts are now ordered, I hope that any P3 will do (as I ordered somewhere else, and that I not run into software problems!

Alert! Raspberry does not equal Arduino. While Raspberry is a micro-computer running linux, Arduino is an old fashioned micro controller.
Long story short, do not order a raspberry pi (or undo while you can).
Please get an Arduino Uno R3 (yes, any should do).
Do not get a Raspberry Pi (none will do).

[RonR]

Many thanks for coming up with this Matt,

I used a metal case meant for an Arduino Mega, which gives some room for extra circuitry and connectors at the rear. On the left is the 'Paperclip' switch.

IMG_20171101_small.jpg

A note for other builders:
I used the prototyping area on the logger board to build the ALDL interface circuit so it's hard wired to the Tx and Rx pins. However after doing this I got the error - "Avrdude Stk500_getsync(): Not in Sync Resp=0x30" when uploading the sketch - This error can sometimes appear when something is connected to the Arduino Rx pin. Unplugging the logger board allowed me to upload successfully.

A more permanent solution would be to use a dual pole power switch, the second pole could be used to connect the Rx pin when switching on the +V from the ECM. The switch can be off when connected to a PC as the Arduino is powered from the PCs USB port.

A few ideas for further development:
A small remote display providing a selection of Elanscan data every 2 seconds or so. (Display ordered - project for winter)
Powering the logger from an ignition switched source, then either:
a. Use a push button to start or stop logging.
Or b. Extract the "Engine Running" flag from the ECM data and log every journey automatically.

Cheers,
Ron

[matts1972]

A few ideas for further development:
A small remote display providing a selection of Elanscan data every 2 seconds or so. (Display ordered - project for winter)
Powering the logger from an ignition switched source, then either:
a. Use a push button to start or stop logging.
Or b. Extract the "Engine Running" flag from the ECM data and log every journey automatically.

That's the spirit
I also have thought about logging every journey. A 2GB sdcard is big enough for years of ownership. You would 'only' have to solve the issue of not draining too much battery power while parked.
Cheers,
Matt

[RonR]

A quick update on mods to this project:

1. Transistor buffer interface between ECM and Arduino - I'm currently testing this, it puts less load on the Arduino's RXD and TXD pins, so allows sketches to be uploaded whilst connected. Just 4 transistors and 6 resistors in the circuit.

2. Permanent Connection - Possible using a feed from the ignition switch, a Relay and a turn-off delay circuit to enable the logger SD Card file header to be written and the .ecu file to be closed before losing power. According to LTSpice there should be a battery drain measured in micro-amps when the Ignition is switched off:

Relay-Delay-LTSpice-sm.jpg

3. Information Display - First tests of the 2.2 inch screen look promising, but I still have to work out how to extract the data coming in from the ECM:

Display-Test2.jpg

Cheers,
Ron

[John_W]

Wow!
No idea what you guys are going on about, but keep it up chaps, and tell us all when it’s finished.

[HJ2]

I love it!
Still waiting for my (correct) parts ...

[Giniw]

3. Information Display - First tests of the 2.2 inch screen look promising, but I still have to work out how to extract the data coming in from the ECM

It's not very hard, the info can be read easily in the elan scan ini file =)
=> data offset, data size (byte or short mostly), signed/unsigned, formulae to display human readable value (if I remember correctly its only a addition and a multiplication)

[Fetnas]

This is AWESOME!
I've been thinking about trying to do something like this myself but the learning curve just seemed too steep with my very limited programming ability. I can get an Ardunio light to flash and have it print "Hello World", but that as far as I've progressed.
I will defiantly be putting one of these together and look forward to seeing the further development.

LEC is the BEST car forum out there! Brilliant work Matts1972

[RonR]

Just a quick update on the Display Mods:

1. Transistor buffer prototyped and working - Uses an Arduino Digital Pin to control when to "Listen" to the ECM. Allows new sketches to be uploaded whilst the circuit is connected to the Arduino RX pin.

2. Relay delay circuit tested and working - Allows Ignition switch to control the power to the logger, giving a ~7 second turn-off delay, enough for the logger to realise that the ECM isn't talking, Re-write the header, close the Log File and say goodbye.

3. Information Display - Extract of info from the ECM datastream tested and working, including error codes. A rough-and-ready instantaneous MPG (or Km/L) figure is calculated from Speed, RPM and Injector Pulse Width. The screen layout has been cleaned up somewhat, Date/Time added, and compiler options added for UK, US and ROW displays:

UK-Test.jpg

US-Test.jpg

ROW-Test.jpg

Last few problems to solve:

a. Fitting all variables into the Arduino's 2K area, especially as around half that is taken up with SD Card stuff. Results can be "Unpredictable" if there's not enough room!
b. Changing SD Card error code to display to the screen rather than the serial port - this may buy me some of that 2K back.

Some other ideas which may or may not work.....

Identify PROM and whether an upgrade has been fitted (Everest, Elysium, etc).
Rev limit warning light (No problem implementing the light, but would a ~1/4 second delay be acceptable as we're getting the info at 8192 baud through a serial link?).
Reverse display output for HUD reflection in Windscreen.

Cheers,
Ron

[HJ2]

wow Ron!

[matts1972]

Just a quick update on the Display Mods:

Thank you, Ron. Looking forward to beta test - as soon as my Elan comes out of hibernation in April

[Bern]

I've built one of these, and all appears to be working correctly, but I get a .ecu file that contains 266 NULLs then a "G" and then some more NULLs!

I'll see if I can create a debug file on the card and write to it so I can get an idea of where it's going wrong.

Nice work though Matts, I'm thinking of other things I can do with a Arduino now....

Cheers,

Bern.