A CSV record can span two physical lines.
The checker links findings to the physical starting line of a source record, including the header. A quoted newline belongs to a field. It does not start a new component record.
These synthetic UTF-8 CSV snippets deliberately contain one multiline comment, one duplicate placement and one missing placement. They demonstrate parsing and traceability, not a manufacturing submission.
Paste the BOM exactly
Designator,Quantity,Populate,Comment
R1,1,yes,"First line
second line"
R2,1,yes,SecondThe opening quote follows yes, on physical line 2; its closing quote follows second line on line 3. Preserve both. R2 therefore starts on physical line 4. The BOM contains two data records, not three.
Paste the CPL separately
Designator,Mid X,Mid Y,Rotation,Layer
R1,0,0,0,Top
R1,1,0,0,Top- Select Read columns.
- Map BOM reference to Designator, quantity to Quantity and population to Populate.
- Map CPL reference to Designator, X to Mid X, Y to Mid Y, rotation to Rotation and layer to Layer.
- Select millimeters and factory-neutral consistency, then Run check.
Expect two blockers
| Finding | Source button | Meaning |
|---|---|---|
| duplicate-cpl | CPL line 3 | R1 already appeared on CPL line 2. The second placement is a duplicate. |
| missing-placement | BOM line 4 | R2 is populated but has no CPL placement. |
The report counts 2 BOM rows, 2 populated references and 1 unique placement. The duplicate R1 does not create a second unique placement. There are 2 blockers and 0 warnings.
Open BOM line 4 to inspect R2. Calling it spreadsheet row 3 would lose the original text position because a spreadsheet displays the quoted multiline comment inside one cell. Source buttons use the original input's physical lines, not the current issue-table position.
Correct the source, then rerun
Confirm the intended board revision and population. If R2 is fitted, regenerate a coherent placement export that includes it and removes the unintended duplicate R1. If R2 is intentionally absent, express its population intent explicitly. Do not rename the duplicated placement to R2 without verifying its coordinates and identity in CAD.
Unclosed quotes or unequal column counts block parsing instead of producing a partial report. A comma inside a field also needs quotes; a literal double quote inside a quoted field is written twice. This app accepts strict comma-separated UTF-8 CSV, not XLS/XLSX or arbitrary delimiter formats.
JLCPCB's preparation guidance explains the reference-alignment objective. Multiline parsing and physical-line reporting are this checker's documented behavior. No clean consistency result validates polarity, centroid, footprint orientation or factory acceptance.