BOM and CPL handoff guides

Small discrepancies are easier to fix when the report points to an exact source line. These guides explain what the checker tests, how to reproduce each result and which decisions require your CAD drawing or factory preview.

• Trace multiline CSV records to physical source lines

  Copy a two-record BOM and duplicate CPL, then verify exact source buttons and report counts.

• Trace a missing KiCad placement upstream

  Work through a missing capacitor, footprint/export exclusions, population intent and a coherent replacement export.

• Find missing and duplicate BOM/CPL references

  Expand grouped designators, separate row counts from reference counts and trace a mismatch to its input line.

• Handle DNP and assembly variants without hiding errors

  Express population intent explicitly, avoid inverted DNP flags and understand why a DNP placement remains a warning.

• Check CPL units, rotation and board layers

  Validate coordinate syntax with explicit units while preserving the boundary between numeric checks and physical orientation.

• Use the limited JLCPCB basic CSV preflight

  Understand the supported header, unit and reference checks and the factory decisions this tool cannot make.

Examples are synthetic, per-board data. They are not production files or a factory-approved assembly package.

Open the checker or review the source register and support limits.