Open a datalogger CSV and actually read it

It opens the files real loggers write

A datalogger export is not the tidy CSV most tools assume. Every one of these was a file that used to come out empty:

• MoTeC, AiM, VBOX, RaceChrono and HP Tuners all write metadata above the header — session name, date, firmware — so the header is found by shape rather than assumed to be the first line.
• A units row under the header is common, and parsing it as data used to put a row of NaN into every channel and drag its statistics with it.
• European exports use semicolons with a decimal comma. Read as a normal CSV, every channel comes out empty — and then gets hidden as flat, so the file appears to load and shows you nothing.

The delimiter is chosen by which one gives a consistent field count across a sample of lines, not by counting characters: in a semicolon file the decimal commas outnumber the separators.

Reading it

Channels stack as separate panels against time, each with its own scale, because a 0–5 V sensor and a 0–8,000 rpm trace share an axis badly. One crosshair runs through all of them, so a dip in oil pressure and what the throttle was doing line up without counting pixels.

Zoom into a corner and every panel zooms with it. The statistics panel then reports minimum, maximum and mean for that window rather than for the whole session — which is the number you want when the question is what happened between the braking point and the apex.

Two other panel types when time is the wrong axis: scatter, for one channel against another with an optional third as colour, and histogram, for how long something spent where. Gear against speed, or how much of a lap was actually at full throttle.

Replay

Play the cursor through the log at a speed you choose and the window scrolls with it, so a long session can be watched rather than scrubbed. Useful for finding the moment something let go, when you know roughly where but not exactly.

What it is not

It is a viewer, not an analysis suite. There is no lap detection, no track map, no comparison of one lap against another, and no maths channels. If you need to overlay two laps of the same corner, this is the wrong tool and MoTeC i2 is the right one.

It reads CSV. Proprietary binary formats — .ld, .drk, .vbo — need exporting to CSV from the software that wrote them first.