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Binary32 compatibility

Binary32 is the IEEE 754 single-precision floating-point format commonly represented by C float on embedded systems. It has less precision than the binary64 floating point normally used by Python.

rtd-sensor does not simply assume that a single-precision implementation will be “close enough.” Its binary32_compatible conformance profile is based on independent single-precision evaluation and explicit acceptance criteria for the behavior covered by that profile.

Built-in binary32 profile available since: rtd-sensor 0.5.0. Characterized IEC 60751 reference-resistance coverage added in: 0.6.0.

Why this matters to an MCU

A constrained target may want only:

Pt100
resistance → temperature
binary32_compatible

That can be a legitimate subset claim without implementing the complete Python package.

What the claim does not mean

binary32_compatible does not mean:

  • every arbitrary user coefficient set is safe in binary32;
  • every future model family is automatically covered;
  • binary32 and binary64 are bit-identical; or
  • the physical sensor uncertainty is determined by floating-point precision.

It means the implementation satisfies the published numerical acceptance for the specific claimed contract subset.