Import STDF Test Data

STDF (Standard Test Data Format) is the de-facto datalog format for semiconductor ATE. It is a structured format: TofuPilot reads its records directly, so importing an STDF file needs no column mapping. Each tested device becomes a Run with its tests and limits intact.

Use this to pull data straight off Teradyne, Advantest, Cohu, or SPEA testers without re-running anything.

History

Teradyne's Semiconductor CIM Division developed STDF in 1985 as a vendor-independent way to log semiconductor ATE test data, originally on UNIX testers. Refined with input from six ATE vendors and 22 customers, it became the de-facto industry datalog standard. The current release is Version 4 (V4-2007); SEMI distributes the spec under license.

File structure vs the TofuPilot model

STDF is a binary, record-based format. A file opens with a FAR record and closes with an MRR, and every record starts with a 4-byte header (REC_LEN, REC_TYP, REC_SUB). TofuPilot reads the part and test records and maps them onto the run model.

A multi-part STDF file imports as one run per part, so a full wafer or lot lands as a batch of runs in a single import.

Prerequisites

• An STDF v4 datalog file (.stdf).
• A Procedure to attach the runs to, created in the dashboard.

Auto-detection

TofuPilot detects STDF by its binary record header (the FAR record at the start of every v4 file), not by file name. On the import page the row shows Auto-detected as STDF; override the format from the row's detail sidebar if detection picks wrong.

Import from the dashboard

1. Open the target procedure's import page.
2. Drag your .stdf file onto the dropzone. The row shows Auto-detected as STDF and a Ready status.
3. Click Import. The runs appear under the procedure.

Drop multiple datalogs at once to import a batch; each is parsed independently, so a single corrupt file won't fail the others.

Import through the API

Upload the file, then import it by upload_id with the STDF importer.

# Import an STDF datalog (upload_id comes from the upload finalize step)
curl -X POST https://tofupilot.app/api/v2/import \
  -H "Authorization: Bearer $TOFUPILOT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "items": [
      { "upload_id": "550e8400-e29b-41d4-a716-446655440000", "importer": "STDF" }
    ]
  }'

The endpoint returns a { results: [...] } array with one entry per item. Pass several files in the items array (up to 100) to import them in one call; each is parsed independently and reported per-item. See the REST API reference for the upload flow and response schema.

Format

STDF is a binary V4 datalog. For a human-readable equivalent, see ATDF.