Designing Firmware That Survives the Field
Lab conditions lie. Firmware for industrial devices has to assume power loss, electrical noise, and years of uninterrupted operation.
A device that works perfectly on the bench and fails in the field is one of the most expensive outcomes in embedded engineering, because the cost of diagnosing and replacing hardware on-site dwarfs the cost of writing more careful firmware in the first place.
Assume power will be cut
Industrial power is not clean, and devices lose power without warning. Firmware has to assume this and handle it: writes must be safe to interrupt, state must recover cleanly on restart, and no single power cut should ever corrupt stored data.
Expect electrical noise
Near motors and heavy machinery, signals are noisy. Robust firmware debounces inputs, validates readings, and rejects impossible values rather than passing them upstream where they become bad data in someone's dashboard.
Design for years, not demos
A field device may run untouched for years. That means watchdogs to recover from lockups, remote update paths for fixing issues without a site visit, and memory management that does not degrade over long uptimes. These are the details that separate a product from a prototype.