Layout Pcb

Generate component placement, autoroute via Freerouting, run DRC, and export review images. Human reviews at the end.

Prerequisite (human, one-time)

"Update PCB from Schematic" is GUI-only — no CLI or Python API exists for this.

1. Open pcbnew: uv run poe inspect-asm
2. Press F8 (Tools → Update PCB from Schematic)
3. Click Update PCB — footprints appear piled at origin
4. Save and close

This only needs to happen once per schematic change. After footprints are on the board, this skill handles everything else.

Phase 1: Generate Placement

Step 1: Extract connectivity

Read the netlist from the PCB to understand which components share signal nets:

python3 -c "
import pcbnew
from collections import defaultdict
board = pcbnew.LoadBoard('cad/cm4_carrier.kicad_pcb')
net_to_refs = defaultdict(set)
for pad in board.GetPads():
    net = pad.GetNetname()
    ref = pad.GetParentAsString()
    if net and net not in ('GND', '+3V3', '+5V', ''):
        net_to_refs[net].add(ref)
edges = defaultdict(list)
for net, refs in net_to_refs.items():
    refs = sorted(refs)
    for i in range(len(refs)):
        for j in range(i+1, len(refs)):
            edges[(refs[i], refs[j])].append(net)
for (a, b), nets in sorted(edges.items(), key=lambda x: -len(x[1])):
    print(f'{a} <-> {b}: {len(nets)} nets: {nets}')
"