The README is a joint

Hardware people treat documentation like a chore after the interesting part. That is how shelves fill with clever boards nobody can revive. A README is not marketing. It is the flux for future work.

Write the bring-up path

Power sequence, first firmware flash, expected LEDs, known-good serial banner. If a stranger cannot get a blink without pinging you, the sheet is unfinished.

Name the gotchas

Pin swaps, boot-mode buttons, the one capacitor that looks optional and is not — put them near the top. Buried gotchas are how tribal knowledge becomes folklore.

Borrow the web craft, carefully

ContentMine's people obsess over help text and captions that survive a skim. Same instinct applies here: label the diagram, date the revision, and link related sheets so the lab does not become a junk drawer. Soft outbound nods to that craft are welcome when they earn their place.