Nit 1.3.1 Software - Windows based ECU Editor (Free with development donation) Use with N72

Works with: Windows 10/11 PC; .bin, Intel HEX and Motorola S-record ECU files; 67-column map-list CSV exports and tuning-suite scripts; TunerPro XDF definitions, including N72 definitions; ASAP2 A2L descriptions. Automatic checksum correction for Hyundai/Kia SIM2K-250 (606Z0, 606A1, 606A4) files.

What this is

Nit 1.3.1 (formerly N75 ECU Editor which is still 100% completely free to use (Link at the bottom of any page - Nit runs on the same style - Free to use our standard editor - Free to use with development donation for Nit - this is the same model TunerPro and TunerPro RT runs on)) is an offline ECU calibration map editor for Windows from N75 Motorsports. It opens your binary, shows the maps your definition describes, lets you edit them in Table, 2D, 3D, Hex and Binary views, corrects SIM2K-250 checksums when you save, and exchanges map lists and tuning scripts with other tuning software. XDF and A2L definitions import directly, and the editor also builds definitions itself with a map finder and a classic tuner hexdump. To upgrade, login to your account view your orders, download the newest version.

It is free with a development donation: your order funds development.

New in 1.3.0: the project workflow

Version 1.3.0 is about everything around the map: definitions from an A2L, a database of your files, map packs and scripts that finds the right pack by itself, versions of a tune inside one project, and maps taken over from another binary.

• A2L import (Driver > Import A2L, or drop the .a2l on the window): every characteristic becomes a map, with data type, byte order, row or column layout, conversion, units, axes and the folder tree taken from the A2L. A2L addresses are ECU addresses, so Nit proposes base offsets from the A2L's memory segments, EPK and address bits and scores each one against the open file: how many maps land inside it and how many axes read strictly monotonic, live as you type a base. A real SIM2K-250 A2L with about 17,000 objects is detected as base 0xA0000000. The report lists what was imported and what was skipped, and why.
• Database (Project > Database, Ctrl+Alt+D, or the Database toolbar button): one searchable, sortable window with four tabs. Projects; Files, your library of original reads with the software and calibration ids found in them (for example 111606A1T3000000); Map packs, with a match score for the open file; and Scripts, every script you applied, created or exported, ready to re-apply to the next car.
• Automatic map-pack detection: when a file opens, every map pack in your library is scored against it: same fingerprint, same size, the pack's software-id strings found in the file, and its axes reading monotonic. 85 % or better loads by itself, 30 to 85 % is offered with a Load button, and a pack made for another software version of the same ECU scores low instead of loading the wrong maps (an Elantra N pack scores 22 % against a Stinger file).
• Project versions: Save as new version (Ctrl+Alt+V) snapshots the modified file with a name and a comment: stock read, stage 1, stage 2. The Versions list opens any version, makes one the original, renames, exports it as .bin or deletes it, and versions travel in the project bundle.
• Organise the map tree: Ctrl+click and Shift+click select several maps; drag maps or whole groups to move or nest them; New group from selected maps, Move to group and Delete work on the whole selection.
• Copy map values from another binary (Tools menu): take maps over from a donor file, another tune or another read of the same software. Every map is checked first and listed as differs, identical or out of range with its changed bytes; pick all, the differing ones, the tree selection or single maps, optionally with the axis bytes, and copy them as one undo step.

Scripts and map packs: apply them, make them

Nit works with the two files a tuner handles every day, map lists and tuning scripts, so a tune moves freely between your tools.

• Apply script (Tools menu, the Script button, or drop a tuning script on the window): the script's search blocks are located by their original values, at the stated address or at the best match anywhere in the file, so a script written for another software version follows the moved maps. You pick the replace mode the script offers (absolute, difference or percent), review the per-map report (found, moved, not found, cells to change) and apply it as one undo step. Scripts N75 supplies apply the same way, and map definitions carried by a script are added to your driver.
• Create script from differences: every changed map becomes a genuine-format script, search on the original raw values, replace in all three modes, ? for cells you did not touch, optionally with the map definitions. Apply it in your other tuning software, send it to a customer, or keep it as the portable record of a tune.
• Map-pack scripts: export a map, a group or the whole driver as a definition-only script that imports your maps into another tuning suite's project.
• Import map pack (CSV): an "Export as CSV" map list (the 67-column Name;IdName;FolderName;Type file) becomes the driver, folders and all. Data type, byte order, scaling, precision, units and axes come straight from the CSV; nothing is guessed. With a file open every map that carries values is decoded and compared, and the dialog reports the match count. cp1252 and UTF-8 exports both read, so degree and micro signs survive.
• Export map pack (CSV): your driver as the same 67 columns with values from the open file, ready for import in your other tools.
• N75 map pack (.n75pack), new in 1.2.4: Driver > Export N75 map pack writes your driver as an encrypted, tamper-proof pack that opens only in Nit. Sell or share map packs without giving away an open definition file: Nit opens them by drag-drop or Ctrl+D, any other tool sees only sealed data, and a modified pack is refused.

Checksum correction for SIM2K-250

When a Hyundai/Kia SIM2K-250 file opens, Nit identifies the ECU family and reads every checksum field the ECU verifies, with no setup. Profiles in this build: SIM2K-250 606Z0 (Kia Stinger 606E3, Veloster N 606E4 / 606G1, i30 N 606D5 / 606F2, Sonata 606G1) and SIM2K-250 606A1 / 606A4 (Elantra N, Kona N, Veloster N software 606T* / 606U*). The status bar shows the state, for example "Checksums: SIM2K-250 606Z0 - 7 OK". F2 lists every field with its stored and computed value, Alt+F2 corrects them as one undo step, and "Correct checksums on save" (on by default) fixes them before the file is written. Boot-loader CRCs are verified, never written; a file whose boot CRC does not verify is refused rather than guessed.

Other ECUs show "no profile" and save as-is. A driver can carry its own checksum definitions (byte and word sums, XOR, CRC-16 and CRC-32 variants) and the Checksum search finds the algorithm behind a stored value; automatic correction is offered for the SIM2K-250 families above only.

The classic tuner hexdump

New in 1.2.1–1.2.4: the Classic colour mode, a real 8 / 16 / 32-bit Width in the Hex view, and bin-to-bin compare. One click (Colour > Classic) turns the Binary editor into the classic tuner hexdump: black background, green values zero-padded to the width of the type (085, 05717, 0374675029, or 2 / 4 / 8 hex digits in the Hex display), 16 bytes per row at 8-, 16- and 32-bit width, the bytes of every map on blue and their axes on dark blue, a character column at the right, and the selected map framed in red with its badge (name @address: cols x rows (bits)). Dec, Hex and Bin displays and the Signed switch all work in this mode, and your own column layout comes back when you switch to Heat. The Hex tab reads the same way: its Width select groups the dump into 4- or 8-digit words (# cycles the width, Ctrl+E flips Hi-Lo / Lo-Hi), the byte order is taken from your driver's maps on the first switch, and double-click edits a whole word as one undo step.

Compare any two binaries. The Hex tab's Diff select compares the open file against its original or against any other bin you pick: every differing byte is printed in light red, the status line counts the differences (for example "338 differing bytes in 183 ranges"), and E / V / N / L or the arrow buttons jump from change to change with the exact bytes selected. Two tunes, stock vs tune, or two reads of the same ECU: the differences are visible in seconds.

The Binary editor shows the whole file as 8/16/32-bit or float values in either byte order, the way tuners hunt for maps: Dec / Hex / Bin number systems, bars beside each row, pale program code so the calibration data stands out, Overview (O) and Preview (P) panels with Tab showing both, Ctrl+B to lock the heat colours to the selection, Rect / Rows / Cols selection modes, drag-to-resize columns, an Offset that re-phases the grid a byte at a time, Sync to follow the map selected in the tree, and scored axis detection when you press K to create a map.

The keys follow the classic tuner layout: W / M and # change columns and width, S toggles signed, A repeats the last value operation (Again), Ctrl+Shift+Up / Down step by 100, Edit > Change by... interpolates four corner amounts over the selection, Del selects nothing and Shift+Del restores the original value. Tools > Classic keys switches the profile; F1 lists every shortcut.

Editing maps

Table, 2D, 3D, Hex and Binary views sit on F5 to F9. The table shows Phys, Raw or Hex as Value, Org, delta or percent, with heat colouring and changed cells in red or blue. 2D curves are drag-editable over the dashed original; 3D draws the surface over the original wireframe.

Selection operations are single undo steps: plus or minus 1, 10 or 100 raw, plus or minus 1 %, Change relative, Change by (corner matrix), Set value, Interpolate (Ctrl+I), 3x3 Smooth, Original value and Again (A). Differences (Ctrl+U) lists changed maps with mean, min and max delta %, changed checksum fields and unmapped byte ranges; E / V / N / L jump between differences.

Finding and making maps

Find maps (Ctrl+M) scans the file for calibration tables by structure: one or two strictly monotonic axes followed by a block of smoothly varying values. It tries 8- and 16-bit types in both byte orders, scores each candidate and lists results such as "0x010040 - 16x16 u16 BE - 0.91" in a Potential maps folder; maps already in the driver are not proposed again. Add to driver makes a candidate a map. In the Binary editor, select a block and press K: the axes are detected and scored for you. Cross-reference map decodes (Ctrl+Shift+M) re-decodes every named map under alternative data types, byte orders and layouts and offers the confident fixes; it changes definitions, never file bytes.

Definitions, drivers and N72

A driver is Nit's map definition file: ECU and vehicle metadata, groups, maps with address, rows x columns, data type, byte order, layout, factor/offset or expression, axes and checksum definitions. The Driver menu covers Import / Export CSV, Import / Export map pack (CSV), Export N75 map pack (.n75pack), Import TunerPro XDF, Import A2L and the library, which detects the matching map pack when you open a file (fingerprint, file size, software-id strings and an axis check). The properties panel edits every field with live validation, with From cursor buttons that take the caret address from the Binary editor or Hex view; right-click a map to copy and paste its properties (units, conversion, digits, min/max, colour and axis settings, never the name or address) onto another.

N72 - Hyundai/Kia ECU Editor is N75's Hyundai/Kia definition product. N72 XDFs import directly, and N75 can supply N72 definitions as map-pack CSVs with full names and groups. Projects keep original, modified copy, driver and versions together; .mapstudio.json bundles embed the binaries so a project moves to another PC.

Coming from another editor

• From the big tuning suites: export your project's map list as CSV and import it; apply your tuning scripts directly; write your changes back as a script or a CSV; switch the Binary editor to Colour > Classic for the hexdump you know, and read the Hex tab in 8 / 16 / 32-bit words.
• From TunerPro: import your XDF; tables, constants, categories and linear equations carry over.
• From an A2L: import it with the base offset Nit detects; maps, axes, conversions and the folder tree carry over.
• Either way: the keys you know (W / M, #, S, T, K, F, O / P / Tab, Ctrl+B, E / V / N / L, Del, A, F2 / Alt+F2) and a Binary editor with bars and pale code.

Features

• Reads .bin, Intel HEX and Motorola S-record; writes .bin and Intel HEX
• Original never modified; editable copy created automatically
• u8, i8, u16, i16, u24, u32, i32, f32; LE or BE; row- or column-major
• phys = raw x factor + offset, or a sandboxed expression with its inverse
• Map-pack CSV in and out (67 columns, lossless, cp1252 or UTF-8)
• Apply tuning scripts (absolute / difference / percent, relocatable search); create scripts from differences; map-pack scripts
• Encrypted N75 map pack (.n75pack): sealed, tamper-proof driver packs that open only in Nit
• Bin-to-bin compare in the Hex view: original or any file, red differences, range counter, E / V / N / L jumps
• Automatic checksum correction for SIM2K-250 606Z0 / 606A1 / 606A4 (F2, Alt+F2, correct on save); driver-defined checksums and Checksum search for other files
• Binary editor: Classic hexdump colour mode (black / green, zero-padded values, blue map bytes, red frame and badge), Dec / Hex / Bin, bars, pale code, Overview / Preview, Ctrl+B range lock, Rect / Rows / Cols selection, go to address (Ctrl+G), ?? wildcard search, Offset to re-phase the grid, Sync to follow the tree selection, Create map (K) with axis detection
• Hex view: Width 8 / 16 / 32-bit words with Hi-Lo / Lo-Hi (#, Ctrl+E), byte order seeded from the driver's maps, whole-word editing in one undo step
• Find maps (Ctrl+M): scored, de-duplicated candidates; Cross-reference map decodes (Ctrl+Shift+M)
• Again (A), Change by corner matrix, plus or minus 100 steps, Shift+Del original value; Classic key profile on by default
• 200-step byte-exact undo and redo; tab-separated copy and paste (Excel-compatible)
• Differences to the original (Ctrl+U) with E / V / N / L navigation
• Import TunerPro XDF and ASAP2 A2L (base offset scored against the open file)
• Database: projects, file library, map packs and script library in one searchable window (Ctrl+Alt+D)
• Automatic map-pack detection when a file opens (fingerprint, size, software ids, axis check)
• Project versions (Ctrl+Alt+V) and portable project bundles
• Copy map values from another binary, as one undo step
• Copy / paste map properties between maps (units, conversion, digits, min/max, colour and axis settings; never the name or address), and From cursor address capture in the properties panel
• Drag and drop of files, and of maps and groups in the map tree; multi-select, new group from selection; tree search (Ctrl+F); F1 shortcut list

What you get

The download link arrives automatically after ordering: a 66 MB RAR, about 67 MB extracted. No installer, no admin rights: extract the archive and double-click Nit.exe (Nit.bat is included as well). It uses the Microsoft Edge runtime already on Windows 10/11. Fully offline: nothing is uploaded. A sample binary, a modified copy and its driver are included. Upgrading from any earlier version keeps your projects and driver library; 1.2.1 and later also open project databases created by newer Nit versions, 1.2.2 fixed the menu bar and toolbar reacting twice to a click, 1.2.4 added the bin-to-bin compare and the encrypted N75 map pack, and 1.3.0 adds A2L import, the Database with automatic map-pack detection, project versions, map-tree drag and drop and Copy map values. Your project database is upgraded the first time 1.3.0 starts. If you go back to a 1.2.x version, export a project bundle first: a 1.2.x Nit that re-saves a project drops its versions. The editor edits files; reading and writing the ECU needs a flash tool. Checksums are corrected automatically for SIM2K-250 (606Z0 / 606A1 / 606A4) files; other ECUs need driver-defined checksums or your flash tool's correction. No file lock-outs: it opens any binary you can read from your ECU.

Getting started

1. Order.
2. Open the download link.
3. Extract the archive.
4. Run Nit.exe.
5. Open the original binary.
6. Let the detected map pack load, import a map-pack CSV, an .n75pack, an XDF or an A2L, or run Find maps.
7. Edit the maps, or apply a script.
8. Save the project, and save a version (Ctrl+Alt+V) at each stage.
9. Save the modified .bin or Intel HEX; SIM2K-250 checksums are corrected on save. Create a script from the differences if you want the tune as a script.

FAQ

Do I need to install anything?

No. Extract the folder and run Nit.exe.

Which files and definitions does it read?

Raw .bin, Intel HEX and Motorola S-record; 67-column map-list CSVs, tuning-suite scripts, .n75pack packs, XDF (TunerPro format), ASAP2 A2L and .driver.json drivers.

Can I use map lists and scripts from my other tuning software?

Yes. Export the project's map list as CSV there and import it in Nit; apply your tuning scripts directly. Nit writes scripts and CSV files your other tools import back, the Binary editor has the Classic colour mode, and the Hex view reads in 8 / 16 / 32-bit words with your byte order.

What is an N75 map pack (.n75pack)?

An encrypted, sealed driver file that opens only in Nit. Use it to sell or share map packs without handing out an editable definition; a tampered file is refused.

Does it work with my N72 definitions?

Yes. N72 - Hyundai/Kia ECU Editor XDFs import directly; N75 can also supply N72 definitions as map-pack CSVs and tunes as scripts.

What if no driver matches my file?

Nit scores every map pack in your library against the file: a strong match loads by itself, a likely one is offered with a Load button. Otherwise import an A2L, a map-pack CSV or an XDF, or run Find maps, create maps and save the driver to the library.

Can I import an A2L?

Yes. Driver > Import A2L reads the ASAP2 file, proposes the base offset that puts its maps on the open file and imports maps, axes, conversions and groups. DAMOS files are not read; use the A2L or a map-pack CSV of the same software.

Does it correct checksums?

Yes for Hyundai/Kia SIM2K-250 files (606Z0, 606A1 and 606A4 software): automatically on save, or with F2 / Alt+F2. Boot-loader CRCs are verified and never written. For other ECUs, no: define the checksum in the driver or correct it with your flash tool before writing the file to the ECU.

Does it write to the ECU?

No. Reading and writing the ECU needs a flash tool.