Bus Debugging

Read the shared embedded contract and keep source/build, device and physical evidence separate.

Read protocol branches. Identify exact controller, peripheral, voltage domain, pins/mux, clock, transfer mode, payload and capture point. Separate electrical, framing, driver and application interpretation. Do not assume a decoded analyzer trace proves voltage margin or signal quality.

Choose a minimal transaction with a datasheet-defined response. Compare the actual wire capture with the requested byte order, edges, framing and timeout. For I2C discovery/pull-ups route to i2c-bringup-diagnostician; use this skill for transaction framing and cross-layer diagnosis. Scans/transfers can write or trigger devices, so keep attached actuators in the required safe state.