Every byte of your ECU, finally readable
Hexx isn't just another hex editor. It opens Intel HEX, Motorola S-record and raw BIN images, decodes them against your A2L into named calibration maps, and lets you edit in real engineering units — then writes back with checksums that always validate. Offline-first.
Every ECU Format
Intel HEX, Motorola S-record (S19/S37) and raw BIN — open, edit and write back in the same format. One editor for every image.
A2L-Aware
Point Hexx at an ASAM A2L and raw addresses turn into named characteristics — no manual address math, no spreadsheet of offsets.
Map-Accurate
Edit 1D and 2D maps in physical engineering units with real axis breakpoints, units and upper/lower limits — not raw byte nudging.
Checksum-Safe
Checksum blocks are auto-detected and recomputed on every write, then validated before flash. Your image stays valid, always.
A Precision Byte-and-Map Editor
Built for calibration engineers who need to see exactly what is in the image — and change it without breaking it.
Byte-Trace Viewer
See the whole image as a continuous trace, not just rows of digits. Switch between 8/16/32-bit interpretation, zoom and pan across memory, jump straight to a 0x offset, and watch highlighted memory regions light up where your maps live.
A2L-Driven Map Extraction
Upload a HEX/A2L pair and Hexx pulls out the calibration maps that actually matter — filtered from thousands of characteristics down to the editable curves and tables, each with its address, axes, units and limits resolved.
Live Map Editor
Edit single cells or whole regions in engineering units, with axis breakpoints and upper/lower limits enforced as you type. Min/max update live, and the byte image updates underneath so the trace and the table never disagree.
Checksum & Integrity
Hexx detects checksum regions in the image and recomputes them whenever you write, then validates the result before you flash. No more bricked ECUs from a stale checksum after a last-minute map tweak.
A hex dump no one can read is not calibration.
Hexx walks the A2L, finds where each characteristic lives in the image, applies its conversion, and hands you an editable map — addresses, axes and units already worked out.
Before
Just bytes. A raw region at an address. No name, no axes, no units — and no way to know whether 0xA2 is a safe value or a misfire waiting to happen.
0x8A40 · 256 bytes · uint8After
A real map. Named, 16×16, axes in rpm and load, values in °CA, limits enforced. Edit a cell and Hexx writes the right bytes back and fixes the checksum — automatically.
A2L-decoded · engineering units · limit-checkedEdit against a Reference, not the void
Every change in Hexx is applied against a Base/Reference dataset, so you always know exactly what moved. Batch edits commit together, and a full diff shows the before/after of every cell — the audit trail your release process expects.
- history Change tracking — every cell edit recorded against the reference, with old and new values.
- dynamic_feed Batch updates — apply a whole region of changes in one atomic write, not cell-by-cell guesswork.
- rule Limit enforcement — upper/lower limits from the A2L keep edits inside the safe envelope.
- hub HELIX-native — the same engine that powers project-linked calibration across the HELIX release lifecycle.
Hexx vs a Plain Hex Editor
The low-level control of a hex editor — plus the A2L decoding, map editing, and checksum safety a generic byte editor never had.
| Capability | Plain Hex Editor | Hexx |
|---|---|---|
| A2L Awareness | Manual address math | Auto-decoded named characteristics |
| Map Editing | Raw byte nudging | 1D/2D cell editor in engineering units |
| Axes & Limits | None | Breakpoints, units, upper/lower limits enforced |
| Checksums | Manual or plugin | Auto-detect + recompute on write |
| Formats | Often one at a time | Intel HEX / S19 / S37 / BIN |
| Visualization | Hex rows only | Byte-trace viewer, 8/16/32-bit, memory regions |
| Change Safety | No validation | Reference diff + pre-flash validation |
| Workflow | Standalone tool | Part of the HELIX calibration lifecycle |
| Deployment | Windows desktop only | Web, Desktop, or Portable |
Built to Fit Your Calibration Pipeline
Run Hexx on its own or as the byte-editing core of HELIX — either way it stays offline and scriptable.
HELIX-Native
Hexx is the hex & binary editing engine inside the HELIX calibration suite. Use it standalone, or project-linked across freezes, reviews and releases with the rest of the lifecycle.
Offline-First
Total privacy. Backend and frontend run locally, so your ECU images, A2L files and calibration data never leave your machine — no cloud round-trip, no data egress.
REST API & Automation
Ingest HEX/A2L, extract maps, apply batch cell updates and validate checksums from your own scripts. The same operations the UI uses are available over a documented local API.
Ready to read every byte of your ECU?
Open a HEX/A2L pair, see the maps appear, and make your first limit-checked edit in minutes — with checksums that take care of themselves.
FAQ
Frequently asked questions
What file formats does Hexx open and edit?expand_more
Hexx reads and writes Intel HEX (.hex), Motorola S-record (.s19, .s37) and raw binary (.bin) ECU images. It pairs any of these with an ASAM A2L (.a2l) description so addresses are decoded into named calibration characteristics. Files are written back in the same format with checksums recomputed.
How is Hexx different from a normal hex editor?expand_more
A normal hex editor shows you bytes and leaves the address math to you. Hexx is A2L-aware: it decodes the image against your ECU description, surfaces named 1D and 2D calibration maps, and lets you edit them in physical engineering units with axis breakpoints, units, and upper/lower limits — instead of nudging raw bytes by hand. It also auto-detects checksum blocks and recomputes them on write so the image stays flash-valid.
Does Hexx keep the ECU image valid after I edit a map?expand_more
Yes. Hexx detects checksum regions in the image and recomputes them automatically when you write changes, then validates integrity before you flash. Every edit is applied against a Base/Reference dataset with batch updates and full change tracking, so you can diff exactly what moved.
Can Hexx work fully offline?expand_more
Yes. Hexx is offline-first. It runs the backend and frontend locally with zero data egress — your ECU images, A2L files and calibration data never leave your machine. It can run as a web app against a local API or as part of the native HELIX desktop suite.
How does Hexx relate to HELIX?expand_more
Hexx is the hex & binary editing engine from the HELIX calibration suite, available as a focused standalone product. Inside HELIX it powers project-linked calibration editing across the full release lifecycle; standalone, it is a precision byte-and-map editor you can point at any HEX/A2L pair.