Framecairn: CAN Decoder

Framecairn is a pocket workbench for decoding CAN frame payloads and sanity-checking bus load — all on one fast screen. Type eight data bytes in hex into the frame field and everything below updates instantly. A 64-bit map colors each bit by the signal that owns it, so you can see exactly where every field sits in the payload. The Decoded fixture section extracts the built-in signals — wheel speed, motor torque, and temperature — applying each one's start bit, length, factor, and offset to turn raw bits into physical values. The Bus budget section estimates utilization at 500 kbit/s: drag the frame-rate slider anywhere from 10 to 3,000 frames per second and watch the load bar, which turns red past 70%. An overlap check confirms the signal definitions never collide. FEATURES • Live hex payload decoding — results update as you type • Color-coded 64-bit ownership map of the frame • Factor/offset scaling from raw bits to physical values • Bus-load estimator with bit-stuffing overhead built in • Automatic signal-overlap detection • Monospaced readouts and VoiceOver labels on every bit cell PREMIUM BY DESIGN One-time purchase. No account, no ads, no analytics, no tracking, and no network access — Framecairn works entirely offline.