Retain width and signedness when converting a raw machine-data integer pattern into a reported number.
Keep the data type
Python’s struct documentation distinguishes signed and unsigned integer formats and their sizes. A raw byte pattern needs an agreed type interpretation. Primary reference: binary integer formats.
A positive or negative display is not determined by the bits alone. The interface contract must also specify width, representation and ordering. The documentation is used to illustrate type distinction, not to assert that an HM controller uses Python.
A hypothetical sixteen-bit pattern
Take the fictional 16-bit pattern hexadecimalFFFF. Interpreted as unsigned 16-bit, it represents 65535. Under an explicitly assumed signed two’s-complement 16-bit interpretation, it represents−1. Those two numbers can arise from the same raw pattern; neither is a measured physical quantity until the field’s actual type and meaning are known.
A different byte order can affect multi-byte patterns, while a scale factor or reserved sentinel can further change the application interpretation. Record those as separate fields instead of diagnosing a process maximum or negative measurement from an unexplained display.
Define the decoding evidence
Keep field identity, width, signedness, representation, raw bytes, byte order, scale and any reserved-value definitions together. Ask for representative expected values on the actual interface and preserve their raw encodings. A test that checks only small positive values may leave high-bit interpretation unresolved.
This guide supplies no controller configuration or conversion code and assigns no data format to HM machinery. It gives the buyer a reproducible type-interpretation worksheet. Counter reset/rollover behavior remains a separate temporal question, and combining words remains a separate sequence question even after the signedness definition is correct.
Customer Questions
CanFFFF mean 65535 and−1?
The stated type interpretations differ.
Does signedness specify byte order?
Ordering is another contract field.
Does the decoded number always mean a physical value?
Scale and reserved semantics also matter.
Primary References
These references support the technical principles discussed in this guide. The worked examples and review questions are educational.
Discuss Your Machine Requirement
Share your product, container, required output and the evidence needed for your technical review.
Request a Technical Review