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[Bug]: Not parsing Channels correctly from Emerald log files #93

Description

@ssaunders420

UltraLog Version

2.15.0

Operating System

Windows 11

ECU Type

No response

Bug Description

when importing emerald log files the channels do not map correctly and the equations turnout wrong. i have attached some logfiles for testing.
channel 1 is correct RPM (Engine Speed), channel 2 should be TPS % (Throttle Pos) channel 3 should be AFR (AFR/Lambda), channel 4 MAP (MAP), channel 5 Advance (Ign Adv), channel 6 Injection Duration (Inj Duration) channel 7 Boost pwm (BoostPWM) and 8 should be load site

logs.zip

Steps to Reproduce

open Application and load attached files and view the channels

Expected Behavior

Parses to correct channels and equations

Actual Behavior

RPM is correct, creates a Channel 2 (ID41) for TPS other channels MAP etc arent in correct places

Error Messages / Logs

No messages

Great App! thanks for sharing!
Cheers
Steve

Screenshots

No response

Checklist

  • I have searched existing issues to ensure this bug hasn't been reported
  • I can reproduce this issue consistently

Activity

  1. SomethingNew71 commented on Sep 27, 2026

    @SomethingNew71
    Collaborator

    Thanks for the report and especially for attaching the logs, @ssaunders420 — and for listing what each channel should be. That mapping is what made this quick to pin down. Glad you're enjoying the app!

    The fix is in #94 and will ship in v2.15.1.

    What was happening: the .lg2 file doesn't store channel names, just an ID number for each of the 8 logger slots. Emerald doesn't publish what those IDs mean, so UltraLog's table was reverse-engineered, and most of it was wrong for your log. ID 41 wasn't in the table at all (hence Channel 2 (ID 41)), ID 1 was being read as TPS, and so on down the list.

    MAP had a second problem. EM Soft stores MAP in whatever pressure unit the logger is set to, and records that setting in the [ValU] section of the .lg2. Your logger is set to kPa, but UltraLog always assumed mbar, so your MAP read 10x low.

    What changed: your log now opens as RPM, TPS, Lambda Sensor Voltage, MAP, Ignition Advance, Inj Duration, Boost PWM and Load Site, in that order. MAP scaling now comes from the [ValU] setting. Your log is included in the test suite, so this can't quietly break again.

    One favour to ask. Emerald doesn't document how two of these are scaled, so I worked them out from your data:

    1. Ign Adv — I'm reading it with a 50° offset, which gives about 5° at idle and 14–17° on full boost. That looks sane for a turbo engine, but I'd like to know it matches EM Soft.
    2. AFR/Lambda — the file stores what looks like the ECU's 0–1 V lambda input, so UltraLog shows it in volts. If EM Soft shows you an AFR number for that channel, I'd like to know what it shows.

    If you open the log in EM Soft and hover at 08:24:12.403, UltraLog reads that point as:

    Channel UltraLog
    Engine Speed 5358 rpm
    Throttle Pos 66.0 %
    AFR/Lambda 0.26 V
    MAP 215 kPa
    Ign Adv 18.0°
    Inj Duration 46.0 %
    BoostPWM 42.4 %
    Load site 12

    A screenshot of that point, or just the numbers EM Soft shows, would let me confirm those two or correct them before the release goes out.

    Docs are on the Supported ECU Formats wiki.


    One note on the sample: your log is now committed to the repository as a test file (exampleLogs/emerald/EM Log MG ZS Turbo boost run.lg1/.lg2) so Emerald stays covered by automated tests. It's just engine data, with nothing identifying in it. If you'd still rather it not be in the repo, say so and I'll remove it — no explanation needed.

  2. SomethingNew71 commented on Sep 27, 2026

    @SomethingNew71
    Collaborator

    @ssaunders420 this is merged and tagged as v2.15.1. The builds for Windows, macOS and Linux will be on the release page as soon as they finish.

    I went ahead and released rather than hold everything up, so the Ign Adv and AFR/Lambda question above is still open. If your EM Soft numbers at 08:24:12.403 don't match, post them here and I'll get the correction into 2.15.2. Let me know how it looks on your other logs too.

  3. SomethingNew71 commented on Sep 27, 2026

    @SomethingNew71
    Collaborator

    @ssaunders420 v2.15.1 is live now. On Windows 11 grab ultralog-windows.zip, extract it and run ultralog-windows.exe.

    Your log should open with all 8 channels named and scaled correctly. Please confirm it looks right on your end. If the Ign Adv or AFR/Lambda numbers don't line up with EM Soft, post them here and I'll get the fix into 2.15.2.

  4. ssaunders420 commented on Sep 28, 2026

    @ssaunders420
    Author
    Image Image Image

    Hiya, thanks for coming back to me so quickly!
    i cant test as the download is flagged in defender see the last SC.
    on the log screen it gives a wideband view of AFR so for that timestamp its 11.60, i have attached a SC of the log screen for reference.
    for the ignition, im not at the car so cant access the settings to check the config but i have attached a SC of the timing map which tbh doesnt help a lot! looking through previous excel sheets i see that the advance has been around 25 degrees on full boost but i dont have any that shows advance on idle.
    is there anything i can do to help identify anything else your missing? im happy to help.
    regards
    steve

  5. ssaunders420 commented on Sep 28, 2026

    @ssaunders420
    Author

    Hi, so i booted a linux live version and it works!
    now windows is flagging .0 and .1 as having viruses! i have run both through sandboxes and no issues.
    bloody windows!

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