Add project documentation

hardware/bom.md

@@ -0,0 +1,26 @@
+# Hardware BOM
+
+## Ordered
+
+- Raspberry Pi Pico 2 W
+- ESP32 2-Channel Relay Board
+- 3.5" SPI Capacitive Touchscreen
+
+## Required
+
+- 2x MAX3485 RS-485 Modules
+- 4x DS18B20 Waterproof Sensors
+- 12V→5V Buck Converter
+- CAT5 Cable
+- Bosch Relay Sockets
+- 30A/40A Bosch Relays
+- Automotive Fuse Block
+- Assorted ATC Fuses
+
+## Future
+
+- Pi Zero 2 W
+- GPS Module
+- ELM327 OBD-II Interface
+- CAN Interface
+- Additional DS18B20 Sensors

hardware/cat5-pinout.md

@@ -0,0 +1,23 @@
+# CAT5 Pinout
+
+Pair 1
+Blue        +5V
+Blue/White  +5V
+
+Pair 2
+Orange      Ground
+Orange/White Ground
+
+Pair 3
+Green       RS-485 A
+Green/White RS-485 B
+
+Pair 4
+Brown       Ignition Sense
+Brown/White Spare
+
+Notes:
+
+- Use twisted pair for RS-485
+- Double conductors for power
+- Spare conductor reserved for future use

hardware/esp32-pinout.md

@@ -0,0 +1,18 @@
+# ESP32 Pinout (Planned)
+
+GPIO 16  Relay 1 (Starlink)
+GPIO 17  Relay 2 (Fridge)
+
+GPIO 4   DS18B20 Bus
+
+GPIO 21  RS-485 TX
+GPIO 22  RS-485 RX
+GPIO 23  RS-485 DE/RE
+
+GPIO 34  Ignition Sense
+
+Future:
+- Additional Relays
+- Additional Sensor Inputs
+
+Final assignments pending exact relay board verification.

hardware/pico-pinout.md

@@ -0,0 +1,17 @@
+# Pico Pinout (Planned)
+
+Display:
+- SPI Touchscreen
+
+Communications:
+- RS-485 Interface
+
+Inputs:
+- Touchscreen
+
+Future:
+- Physical Wake Button
+- Rotary Encoder
+- Status LED
+
+Final pin assignments pending touchscreen testing.