cvpcb has a GUI and is focused on footprint assignments. Reference designators and footprints need to be assigned in the schematic editor then show up in the netlist. I would propose that instead of having cvpcb produce an updated netlist, it update the schematic file instead. This would eliminate the need to write a back annotation tool to update the schematic for board turnon or manufacturing reference. There already is a placeholder (F2) of the component for the foot print in the sch file and the footprint currently can be assigned in EEschema by editing each component instance and it will show up in the netlist. It also would be handy while creating a schematic to include the footprint in the add component cache along side the name.
Adding a vendor part number (VPN) field (F3?) would enable an improved BOM listing. This field would be optional and would show up in the BOM if present. The advantage of a VPN nails down a symbol and footprint. Selection of a VPN defines a specific footprint while the schematic symbol could look like anything the schematic designer likes as long as the pinout is consistant. A VPN enables future creation of a project (or board) only BOM (or library) and could reference a larger company wide parts library (or database). Without this each designer potentially re-invents a symbol/footprint library for each project. Example: part # symbol sect footprint ref manufacture description --------- ------ -- -------- --- ----------- ----------- DM74LS00N 7400 A DIP14 (or N14A) U1 DM74LS00M 7400 B SMP14 (or M14A0 U2 54LS00W 7400 A W14B (or CFP14) U3 Note: this is 3 separate parts and need separate ref designators (Using similiar but different parts can happen) Parts with multiple sections only count as one part in the BOM with a shared footprint, the section letter would not be listed. The manufacture, description, inventory could be added to a future, separate parts database, selector, navigator.... The bottom line is the schematic should be the master controlling document...need to swap parts, pins or change footprint? - update the schematic and re-generate the netlist. A more complicated parametric example: Digi-Key Part Number FC0603-50BFTR-ND Manufacturer Part Number FC0603E50R0BTBST1 Symbol: R Description RES 50 OHM 125MW .1% 0603 SMD Manufacturer Vishay/Thin FIlm Resistance In Ohms 50.0 Power (Watts) 0.125W Tolerance 1/8W ±0.1% Lead Style Surface Mount (SMD - SMT) Case 0603 (1608 metric) Packaging Tape & Reel (TR) Composition Thin Film Voltage - Working * Temperature Coefficient * Quantity Available 1 Minimum Quantity 1 Unit Price USD 0.91000 Datasheets here there are many resistors with a common shared symbol and footprint As a designer why do I want to deal with all this? Ans: To make sure the correct parts are ordered, your board is built right, it will work properly and save the company money by ordering common parts in quantity from a qualified vendor. Frank Bennett
