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  1. 3 points
    Simon

    G4x Base map

    For those looking for a base map to have a play with. Software can be found at http://www.linkecu.com/pclink/PCLink 6.15.15.exe Monsoon FW 6.15.6.pclx
  2. 3 points
    TechDave

    Share your Math Channel List

    So this afternoon I sat at the simulator and started mucking about with a few ideas. I wanted to calculate my average speed based on some event, I used a digital input latching on. In the UK we have average speed camera zones, you get snapped at the start and end and they do a distance over time calculation. Often you'll get slowed down by a Karen in an X5 not paying attention, I've always been curious how much I could safely speed up again to catch back up to 50 mph average over the trip. You can do this in log analysis with the statistics view, but this is obviously operating at runtime. So there's a few things here I've done that aren't documented yet, yes they will be. The first is that maths channels can do reassignment, x = x + 1 etc The next is that they're evaluated at 1000 Hz Lastly I know of a few built in functions too. I figured out two methods, of averaging, the first could be used not only for wheel speed, but for really any parameter, lambda, throttle position, you could use another maths function to find lambda, vvt, boost, etc error then feed that function into this one and have an average of error over some time period. This one uses this algorithm: newAverage = oldAverage + (newSample - oldAverage)/sampleNumber the cnt function is a real good cnt function, it counts 1 per cycle (so 1 per millisecond) while c is greater than or equal to 1, so if you feed it a status which evaluates to 0 OFF and 1 ON, then you're away. If you want to use this for Anti-Lag active we might have to get a bit imaginative about an offset, iirc Anti-Lag OFF = 0, ON = 1, Active = 2...etc I had to add a +1 to cnt because on the first cycle it's 0 and that's div by 0, plus the first cycle is the 1st sample too. The 2nd method I came up with was to calculate distance, which of itself is a useful function, then calculate distance/time, again using that good cnt function: Again using reassignment in the Distance function, multiply speed by 1/100th of a second, of a minute, of a hour to get distance travelled per millisecond (rate is 1kHz), I multipled by status to simply switch it on and off. This gives me km. distance a over time, divide by the same multi as above gets us back to an average. You don't need to use 8dp for this, I was just using it while getting my exponents sorted. My functions agree with each other and track to my expectations, but if you spot an error in my maths then shout out edit: unfortunately this is all in kph as I started running out of characters to add the mph multiplier, I've spoken with engineering and we'll see if we can get the length increased, 2.77e-7 helped a lot, but still lost a bit to parenthesis too.
  3. 3 points
    Ducie54

    G4x Base map

    As a feature request can we have the option on which Lambda sensor is used for CLL. As example I'm using 5 lambda sensors. One in the turbo dump pipe and 4 in the turbo manifold using a CAN module. The software uses a average for CLL but would be nice to use Lambda one so manifold pressure is not an influence. Currently to get around this from happening I've set the 4 CAN lambdas as CAN TC.
  4. 3 points
    Simon

    G4x Base map

    Yep Multi fuel and traction control will be coming
  5. 3 points
    Adamw

    What is wrong with my tune?

    I just had a quick look. There is some pretty odd stuff in there. It looks like it has been tuned for flex fuel but there is only one ignition map and no other corrections for ethanol content. Usually E85 can take a heap more advance than petrol so what fuel was that ignition table tuned for? VVT looks like the offsets are set incorrectly. The RH inlet cam is showing 10deg advance when it is in the fully home position. That means it will be getting 10Deg less than what is commanded. The VVT and ignition tables both have big "holes" in them around the cruise area that is going to make it drive pretty horrible. Boost control not working great at all. Fuel control is not great either. I would say this is due to there only being 1 VE table set up, which doesnt usually cover flex fuel well enough especially when injectors havent been flow tested on both fuels. I think the saving grace is you are running it on relatively high eth %, which is relatively forgiving. I wouldnt give it a hard time especially on petrol until it is looked at by someone more competent or interested. If you want to PM me the tuners name I will pass it on to the right people to consider.
  6. 2 points
    I wanted to share my success using a bluetooth adapter since I have not seen any other posts about using one on this forum. So far I have only tested it with an Android tablet and RealDash. It has been working perfectly. Connection is fast and very reliable. There is no noticeable lag on the dash interface. There are a few advantages of using Bluetooth over USB for a tablet dash. 1) The usb port on the tablet is freed up to be used for charging (this can also be used to automatically turn the tablet on/off with key power) 2) The usb port on the ECU can be dedicated to the Laptop usb cable for tuning (dash cannot be used simultaneously with laptop, but less plugging/unplugging) This is assuming that your Link ECU has separate tuning and CANBUS ports. The Bluetooth Adapter I have been using is one made for Megasquirt MS2/MS3 – PerfectTuning is the manufacturer. https://perfecttuning.net/en/accessories/26-bluetooth-adapter-for-ms2-and-ms3.html There are a few other BT adapters for megasquirt, they are all likely the same Bluetooth chip and work the same. The Megasquirt uses a DB9 connector for serial connection, so that is what comes with the BT adapter. In order to connect to the Link you will need a Link CAN connector http://dealers.linkecu.com/CANF_2 These connectors need to be soldered and can be somewhat difficult due to their small size. Cable pigtail is also available but fairly expensive. The following is the pinout on CAN connector, the BT DB9 connector and where those wires need to end up. This can be wired a few different ways. Either the DB9 connector on the BT adapter can be mated to with a female DB9, or it can be cut off and hardwired (or use a different style connector). The two serial wires will go to the CAN connector on the ECU (TX to RX, and vice versa). The 5v and GND wires will need to go to a 5v power source. Do not use the 5v supply from the ECU, the BT adapter can draw up to 30mA. 12V DC to 5V power supplies are very common, it is the same voltage as USB chargers. What I did was buy a USB charger and hardwire a USB cable pigtail to make the connection. I used and like this model: I recommend powering the 5v power supply from the ACC terminal (radio power) on the ignition switch. This way there is still power to the Bluetooth with the key in position 1 (ignition off). This will allow you to power cycle the ECU without killing power to the Bluetooth adapter – leaving it wirelessly connected to the tablet. This means that the dash will be live in about a second instead of 5-10sec. In order to use the tuning port to connect a laptop, either the CAN connector must be removed or a 2 pole switch/relay must be put on the serial wires coming from the CAN connector. The switch must be within about 20cm of the ECU, otherwise the serial stream may become active and not allow the laptop to connect. Once the laptop has been connected, the ECU must be restarted to allow the serial stream to become active again. Hopefully in the future this can be changed by Link so that the serial stream is reactivated upon laptop disconnect. If there is interest and the forum allows, I could possibly make and sell a plug-and-play Bluetooth solution for the Link G4+. Cost would likely be just a little more than the Perfect Tuning adapter. Here is a video of my dash on a “cold start” – Powered up and connected in less than 10 seconds. Realdash can be set to allow the tablet to sleep when charge power is killed from the tablet. It works well as a OEM style dash and I don’t need to manually touch the tablet at all. This is what the inside of the PT BT adapter looks like. Blue = 5v Orange = GND Grey = RX Yellow = TX
  7. 2 points
    Thanks guys for the quick response! I have to say the help documentation is some of the best I've ever seen for a bit of control equipment. Keep it up!
  8. 2 points
    Confused

    cut at 5k rpm (log inside )

    Also, if you press the H key on your keyboard, that will enable colours on the table - these sharp transitions should stick out like a sore thumb, as you'll not get a nice smooth gradient, but a sharp transition from green to red in this case.
  9. 2 points
    You are correct, spark duration and arc duration are the same thing. In your case this setting may only just start to come into play a high rpm. The spark duration setting usually only comes in to play when you have a distributor with single coil and more than 4 cylinders. It is used to shorten the dwell at high RPM when there is not enough time to both charge the coil and spark for the full duration. As an example think of a V8 with a distributor running at 6000RPM. At 6000RPM one engine cycle (two crank revs) takes 20ms. All 8 cylinders have to fire in that time. Lets say your coil needs 2ms of dwell to charge and the spark lasts for 1.0ms. You have to do that 8 times in those 2 revolutions, 8 x 3ms = 24ms - but wait - you only have 20ms to do that in? The ECU cant do anything about the spark so if it knows how long the spark needs and there is not enough time then it can shorten the dwell to make everything fit into the time that is available. A rotary in direct spark mode at 8000RPM will have 7.5ms of cycle time to charge and spark. So if you have a spark duration of 2.9ms that leaves you with about 4.6ms for dwell. You generally dont need much more than 3ms on those coils unless very high boost or Methanol. With it set at 2.0ms now is not a big problem because as you can see it is quite likely you are not running into cycle time issues anyway.
  10. 2 points
    Adamw

    Knock strategy with sequential gearbox

    Here's a quick video to give you an example. Gear shift knock.mp4
  11. 2 points
    You can connect both 5v and 12v sensors (and VR sensors etc that have varying voltage output) all to the same sensor ground. The reason to chose 1 type of ground over another is not input voltage, but more: 1) how stable does the signal need to be for the engine to run well (crank trigger = really important, any of the temp sensors = not a big issue if the signal bounces around a few percent). And as part of this, will a ground offset cause an incorrect reading that still looks legit. (eg voltage offset on any analog sensor) 2) How much load is expected to go through the ground circuit. eg do not use a sensor ground as the ground side for a vtec solenoid or anything like that. As long as everything on the sensor grounds is low *current* then adding a flex fuel sensor to sensor ground wouldnt hurt, and generally anything that is an ECU *input* you would lean towards putting on the sensor ground circuits. But if you do see issues that seem like sensor noise once you add it, you can probably move the flex sensor to use a direct ground and not see too many issues. These dont report an analog output anyway so should work just fine with slightly noisy voltage/ground.
  12. 2 points
    Brad Burnett

    AEM Water/Meth Boost Safe

    Can wire that wire into a digital input on the ecu. Then could configure the ecu to change boost, timing, and fuel values when that is active.
  13. 2 points
    TechDave

    Fuel film modelling in G4X line

    Accel fuel has been changed to a simplified X-Tau model
  14. 2 points
    Ducie54

    G4x Base map

    Is it possible to have a Math block drop down box with the maths all ready worked out?
  15. 2 points
    TechDave

    G4x Base map

    @Ducie54 I get that if I haven't turned on a fuel mode yet. Switch on a fuel mode and you get it, I'll add a note to the engineers to show a message "no fuel mode selected...blah blah etc"
  16. 2 points
    Simon

    MR2/ST205 and Knock

    Highly likely.
  17. 2 points
    I think with engine temps of 10°C and 94% ethanol you are going to struggle with cold start and there will be little you can do from a tune perspective to help. The vapour pressure of straight ethanol is very low so there will barely be any vapor in the port at that temp no matter how much fuel you dump in, it will just remain as liquid. Somewhere below around 10°C there is not enough vapor produced to support combustion. This is the reason why pump E85 gets reduced to E60-E70 in winter so there is a little more of the volitile solvents available to create some vapor in the port. In regions like Brazil etc where they predominantly use straight ethanol it is common to use heated injectors to get around the problem.
  18. 2 points
    Yep sounds like you got it. Here's a quick demo: https://1drv.ms/u/s!AiYbYlZQuRHPqylX67m5Oo57-JVv?e=t3SK3f
  19. 2 points
    Ok, all the CAN is done, I havent added any of the new channels to displays or whatever but they should now be available. I have kept all the channel names pretty much as per the BPM datasheet. The only one that is a bit ambiguous is Fuel level. He has used 2 bytes like it is expected to cover a large range of numbers but then says the range is only 0-53L. Just one byte can do up to 255 and 2 Bytes is capable of 65000. So I suspect he might be sending it as "0.1L" rather than whole Litres but that is not clear. If your fuel level says "500 Litres" when you have it all working then set the scalar to 0.1. Marvin-LinkG4UpdatedV2Port2CAN Adam.aemcd7
  20. 2 points
    hexdmy

    tps and MAP accel fueling together

    Bumping this topic... I'm surprised no one else has interest in this. OEM systems I have worked with do this, and it makes sense. At low throttle openings, a change of throttle angle is a better trigger for transient fueling than map for engines that have low / noisy idle vacuum. However, at steady throttle angles, on a turbo engine, as the boost builds, there can be a need for additional fueling, otherwise you get a lean spike. I've noticed this when tuning steady state and then doing transient sweeps, if you tune to the sweep, you get a inverse V in your fuel map. Certainly this is not reinventing the wheel, just doing what the OEM's have already been doing for many years, and for good reason.
  21. 2 points
    Yes, Spartan has a termination resistor built in and it is enabled by default. I would use the Spartan in its default mode, use 1Mb/s and 1024 as ID. Use the attached stream definition. From the testing I have performed, the Spartan doesn't actually work in Link mode, the stream appears to be incorrect. (you would have needed to log in via serial bluetooth to change the mode/ID to Link CAN Lambda mode) HTH, Richard. Spartan3ADVDefaultMode.lcs
  22. 2 points
    Richard Hill

    Thunder lambda wiring - 12v

    Here are some measurements from a single 4.9 Lambda sensor running on a Thunder on the bench. The maximum the sensor drew was 1.43A at the end of the heating phase
  23. 2 points
    Adamw

    RPM 65535

    No, the dwell scatter is a symptom of a trigger error. It means the ECU isnt receiving the regular tooth pattern that it expects from the trigger. As I said earlier, the quickest way to find your problem is to get an oscilloscope capture of the triggers - preferably when it is playing up. The Oscilloscope will show us what is wrong with the waveform and this will usually give you some strong clues what is causing it. Do not waste time changing random parts - there could be many hundreds of different scenarios. Your logs show the ECU is not happy with the trigger so you need to start by diagnosing what it is about the trigger signal that the ECU it is not happy about.
  24. 2 points
    Sorry I haven't logged in for ages. Have just seen your comments are re-uploaded photos, should all be good now.
  25. 2 points
    I see, I wish that it would always ask if I wanted to load write the changes to the ecu, no matter how large. Because when it just loads the config out of the ecu and doesn't notify about anything, it's easy to think there were not any changes in the tune file. Then you carry on, tuning the config loaded from the ecu, until you realize there is no filename associated with the open tune file. Then you have to open the old file and see what's different, plus the changes you've recently made to the config file that was automatically loaded.... I've lost a good bit of time this way. If it's not possible for PCLink to ask if you want to load a tune with large differences, there should at least be a dialog that notifies what's going on (tune uploaded from ECU is replacing the open tune).
  26. 2 points
    Simon

    S15 plug in

    Jump on and download the PC link tuning software. The help file will have 99% of your questions covered.
  27. 2 points
    Adamw

    Link monsoon wiring

    I think I would avoid that, it looks very suspicious. Look at the main connector, it is missing the housing and looks like the wires are attached directly to the pins??
  28. 2 points
    Adamw

    ECU Unlock fails

    Someone has done a typo by the looks, The last two characters should be b7, not 67.
  29. 2 points
    Would be nice to be able to see at a glance if edits were additions or subtractions since last marker reset. Say on fuel table you add to a cell than the cell turns blue and if you subtracted the cell turns red.
  30. 2 points
    On my setup I use a 3d table to PWM an engine water pump. After a lot of testing I found using the temp output from the radiator and ECT the best way to control the pump. Takes into account out side temp and vechile speed. Would recommend you try that way to control the thermostat. Ive also connected a 2nd Digital output to the same soild state relay as an override. So if I'm at a set TPS or boost range the pump goes to 100%. After a bit of testing during different conditions I can keep the ECT within 2deg in all situations.
  31. 2 points
    Adamw

    MINI LINK G4+ Borg Warner Speed sensor

    I drew this circuit for someone the other day. I havent tested it myself with a turbospeed sensor so no guarantees but I have used a similar circuit to divide a wheel speed frequency down. Over here you can buy the 4024 binary counter for about $1.50 from Jaycar so I assume they should be easy to find anywhere.
  32. 2 points
    Richard Hill

    programmable logic

    I moved away from using generic dash as it employs a compound CAN message, which can be a bit of a mouthful for both the ECU sending and the device receiving. I prefer to use messages which are split over several CAN IDs such as transmit generic dash 2. The only problem with Generic Dash 2 is there's appears to be a bug in the non driven wheel speed (1 byte assigned, but shows as 0-1000kph, guess the text was copied from generic dash). Not a problem though if you aren't planning on going more than 158 MPH...
  33. 2 points
    Im not sure if you are asking a question or making a statement? Of course the fuel table and ignition tables (and all other tables) will need to be tuned to your specific engine before it will run well. It sounds like you dont even have a good grasp of the basic fundamentals yet so Im reluctant to advise you touch it yet. I would not attempt to tune a turbo car with this level of understanding. I would suggest you start by doing something like the low cost EFI tuning fundamentals course here to get a better understanding of the theory behind it: https://www.hpacademy.com/courses/efi-tuning/ If you try to tune without a good understanding of the basic theories then it will just end in disappointment.
  34. 2 points
    Simon

    [UPDATE] PCLink 5.6.6.3564 (on hold)

    Yes it is now ok to run the current release.
  35. 2 points
    Ducie54

    What is wrong with my tune?

    Another look show it's reducing boost target in higher gears but gear detection is not set up correctly. Your vechile speed is showing when in 0 gear.
  36. 2 points
    Another way to work around the missing inputs on the Thunder (or to divide an input frequency down on other ECUs) is to use a CMOS 4018 IC. No external components required and can be powered from the ECUs +5 Volt supply. To divide by 10, the inverted Q5 output is fed back into the data input pin. I used this last week to divide by 8 on a fury (I fed back the inverted Q4 pin to data) Hope this helps, Richard.
  37. 2 points
    Okay so there are a few stages to setting it up. 1. Wiring Run one wire to the knock1 or knock2 wire on the link loom, and one to sensor earth, polarity unimportant. must must must must use shielded wire. The knock sensor outputs a very low voltage signal that's prone to interference. 2. Initial settings Since you are using the 'wideband' knock sensor and an engine with an ~86mm bore has a knock frequency in the ~6khz range select your Freq Channel as 4-10khz Wide Band. Set Ignition Retard limit to 0 degrees. Set the RPM high and low lockouts however you like. (500rpm likely not ideal for the low setting) 3. Cylinder balancing Your knock sensor is mounted closer to one cylinder than the others. It picks up vibrations, so the vibrations from that one cylinder will give a stronger signal than the others. So what you need to do, is hold the motor at say 4000rpm (no load) and check the signal strength of each cylinder. You can check the signal strength by pressing F12 to get to the runtime values screen and looking at these numbers, knock level cyl 1/2/34 See how in that example above, the numbers are 235 / 160 / 255 /145. You need to get these numbers as balanced / equal as possible. You can adjust the values up or down by tweaking the numbers up and down in Knock control > Cyl setup > Cyl 1/2/34 knk level gain Best to start with a value of 1 for the cylinder that's closest to the knock sensor, and increase the other values to suit. If one of the values reaches '2' (maximum) you can reduce some of the other numbers to less than 1. 4. Non knock noise levels Since the knock sensor picks up vibrations, there are of course vibrations happening even when there's no knock. As RPM increases, the amount of 'natural' background noise increases too. The ECU can tell that knock is happening, because there's an unexpected large spike in the 'noise' from the motor around the time of the iginition event. Soooo, you need to find out what the background noise level is for your engine. According to the manual, a 2 row table with full throttle and 0 throttle is sufficient but this is up to you and how long you want to spend on it haha. So head to Knock control > Knock target, right click on the table and select Axis setup to define your table similar to this (if you want) Then you need to run a datalog through the rpm range at full throttle to see what the values are for this table. (and coast back down off throttle for the zero TP target, although I'm guessing not much knock happens at 0% throttle) Open the datalog and bring up a screen to show engine rpm and the knock level global. Knock level global has a maximum value of '1000'. If you find that you are hitting 1000, you need to reduce the Gain Channel number on the main knock sensing setup page to something a bit lower and try again. Remember that the '1000' has to be the maximum even including allowance for knock which is much stronger signal than the background noise so you need to allow headroom for that too. Once you've established these background noise levels for the motor in your table, increase all of the numbers in the table by 20% to give it a bit of a margin against picking up normal engine noise as knock. At this point, because you've set the maximum ignition retard to 0 degrees in your first step, the ECU isnt taking any action against knock. Now that you've got everything setup though (unless I've missed a step here, haha) you can turn the knock sensing on by setting an ignition retard limit here, to say 3 degrees or 5 degrees or whatever you want: Then as per reccomendations from the manual, it's best to test that knock sensing is working under a scenario that minimises risk of damage to your engine. So you could drive along at low load / low rpm and induce knock by creeping the timing forward until it knocks and you can see from the runtime values table (F12) that it's working. From here, it should all be working awesomely. (No responsibility taken for blown up motor though! This is just what has worked for me) Hopefully it all makes sense though Where are you based / what is the car used for? Keen to hear how you get on.
  38. 1 point
    Adamw

    Knock strategy with sequential gearbox

    You can set up a timer and virtual aux to be triggered by gear shift status and use that timer/aux to increase the knock target to say 1000 for a short time during/after a gear shift. I will give you an example later.
  39. 1 point
    TechDave

    G4x Base map

    Done. Should also be fixed.
  40. 1 point
    Adamw

    1jz vvti tune

    VVT looks pretty normal to me. You should post a log of it running though so we can confirm the VVT is actually working as commanded. Throttle response from idle I would suspect is more related to accel enrichment. Your accel settings look quite a bit weaker than what I have needed with a 2J. I will post a compare below, your settings in black or red text, mine in yellow. Also, your ignition timing looks very weak to me - especially for E20. Probably not the cause of your "poor throttle response" depending what you mean by that but it is going to make it drive fairly lethargic. I dont have any tuning experience with the 1JZ specifically, but comparing to a couple of 2J's I have done, my ignition table has up to 10deg more than yours in the low boost areas and those were on pump gas. On top of that you have a 4D ignition table pulling another 6deg out right through the mid range and transient ign retard table pulling another 4 deg out. So some areas you effectively have 16-20deg less advance than what Im used to seeing for a similar engine.
  41. 1 point
    Adamw

    help to start

    You have both AN Volt 1 and AN Volt 5 set to MAP sensor. For Storm blue if you are using the internal MAP sensor it should be AN Volt 5, you need to turn AN Volt 1 off. Because MAP is reading wrong (220Kpa with engine off), the ECU is applying MAP limit ignition cut (boost cut). After turning off AN Volt 1 please confirm MAP reads same as BAP with engine not running.
  42. 1 point
    Hi, On the default settings I've broken a few sets of E-throttle gears, and I've seen a few other people mention similar. (I've busted 3-4 gears already) So I've been looking at ways to mitigate this. Initially I started just looking at the throttle mapping itself, setting the max and min to 2% and 98% so it's not trying to bang into the end stops. But then realized that the e-throttle clutch can be used to help as well, by softening the clutch near the end stops. So I'm using a table like this, and havent had any breaks since: Perhaps it might need fine tuning on an individual basis to make sure it's not slipping too much near the extremities, but it's tested as working well tracking to its target even with high motor DC / fast accel/decel rates.
  43. 1 point
    cj

    G4+ Supra 2JZ PNP

    sounds like progress. Next thing then is to figure out what FP control settings will make it behave properly. Try changing the polarity of aux2 to high and see if the problem get better/worse. can you hear the fuel pump at idle? Maybe have someone put their head in the boot and check? I'd be tempted to disconnect aux 2 from the ecu temporarily (cut the wire, un-pin it from a connector anywhere between ECU and FP controller), then at idle (so pump is running), connect it to ground, then floating, then 12v and see which connection makes the pumps jump up into high flow mode. From there you can work out what to configure in the ECU, or if you need to add a relay to deliver the right voltage.
  44. 1 point
    Richard Hill

    Knock output signal

    Set up a Virtual Aux to turn on when knock level exceeds your chosen threshold, and then set an Aux out to turn on when the Virtual Aux is active. HTH, Richard.
  45. 1 point
    cj.surr

    Fuel Pump Control ECU

    Just wire the relay(s) low side to an Aux out as a "fuel pump" and it will automatically turn off the relay if engine RPM is 0.
  46. 1 point
    Simon

    Sorry to ask. What software?

    We will need to identify the generation of ECU as a first step. As there is different software for the different generations. A photo of the unit with lid off would be the best bet to identify it.
  47. 1 point
    I would suggest you start by logging a hot start and posting that and your tune file here. https://www.youtube.com/watch?v=_P1LRANeO4A
  48. 1 point
    Adamw

    Co2 boost control

    As far as I remember they only control/monitor/target the dome pressure (top side). Bottom side is still connected to manifold but not referenced at all in the control system. Basically just like changing the spring in the dome. If you have a 4psi spring and you add 30psi to the dome your manifold pressure will control at about 34psi.
  49. 1 point
    Adamw

    CAN Hub

    I think the reason they do a CAN hub is probably because most of their devices come pre-terminated "plug and play". We dont do that so much and most feedback seems to suggest the flexibility is prefered. A CAN bus doesnt need a "hub", the whole system was designed to be a main "trunk" that the devices can just splice into parallel anywhere along the line. A $200 hub is just a very expensive way to splice two wires into 4... But the Haltech hub should work with any bodies CAN bus including Link if you really want to pay that much. I've never used these yet but I've noticed recently you can also get CAN bus specific DTM connectors including "splitter hubs" and terminating caps which could be a nice way to do it if you wanted easy expandability:
  50. 1 point
    cj

    G4+ Mazda RX8 CAN Bus

    This guy has a really good process on how to observe and reverse engineer canbus signals http://bobodyne.com/web-docs/robots/MINI/CAN/MINI_CAN.pdf His example use a mini but the process applies to everything. Its basically push the car through some known states eg press gas pedal, speed up, slwo down, turn steering wheel. Graph the output of each stream of data coming across the can bus, then try to map what you did to something you can see happening on the canbus. I've done this myself on a subaru using one of these https://www.aliexpress.com/item/Dual-Channel-USB-To-CAN-Analyzer-DeviceNET-iCAN-VRMS-CANOpen-J19339-CAN-Analyzer/32359550686.html?spm=2114.search0104.3.1.TSYAka&ws_ab_test=searchweb0_0,searchweb201602_4_10152_10065_10151_10344_10068_10345_10342_10547_10343_10340_10341_10548_10541_10084_10083_10560_10307_10175_10060_10155_10154_10056_10055_10539_10537_10312_10536_10059_10313_10314_10534_10533_100031_10103_10073_10102_10557_10142_10107,searchweb201603_25,ppcSwitch_5&btsid=c137e58f-7221-4cd6-8e73-88f833c9f482&algo_expid=3d31339c-5443-452b-a5c7-85399dba71d8-0&algo_pvid=3d31339c-5443-452b-a5c7-85399dba71d8 It looks really daunting to start with as literally nothing has labels, but as soon as you get your head around which devices are which ID's you can start to focus on things that matter - eg tacho signal has to come the ecu, speed has to come from the abs computer (check wiring diagrams but this is usually true) so you have a pretty good idea where to look, graph each block of data, then look for a graph pattern that matches what you did with the vehicle, then work out the scale of it. You may want to start by watching the ID's that are present and the time intervals of them and disconnecting abs/ecu/body control computer/etc to start with as the first step. Remember you dont have to understand all of it, just the signals you are sending from the ecu or receiving via canbus (eg speed)
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