board: start schematic

board/board.kicad_pro

@@ -229,7 +229,7 @@
       "no_connect_dangling": "warning",
       "pin_not_connected": "error",
       "pin_not_driven": "error",
-      "pin_to_pin": "warning",
+      "pin_to_pin": "error",
       "power_pin_not_driven": "error",
       "same_local_global_label": "warning",
       "similar_label_and_power": "warning",
@@ -408,6 +408,11 @@
     "subpart_first_id": 65,
     "subpart_id_separator": 0
   },
-  "sheets": [],
+  "sheets": [
+    [
+      "0bf1fdd4-5a89-4735-8383-190e40fb0179",
+      "Root"
+    ]
+  ],
   "text_variables": {}
 }

board/board.kicad_sch

@@ -0,0 +1,20 @@
+(kicad_sch
+	(version 20250114)
+	(generator "eeschema")
+	(generator_version "9.0")
+	(uuid "0bf1fdd4-5a89-4735-8383-190e40fb0179")
+	(paper "A4")
+	(title_block
+		(title "phiboard board")
+		(date "2026-01-14")
+		(rev "1")
+		(company "phiwan")
+	)
+	(lib_symbols)
+	(sheet_instances
+		(path "/"
+			(page "1")
+		)
+	)
+	(embedded_fonts no)
+)