Wiring Doc

Task

Generate or update a WIRING.md file for the project at $1 (relative path under packages/<domain>/).

Process

1. Read the project source code to discover pin assignments, components, and peripherals:

   • main/*.c and main/*.h — look for #define pin assignments, gpio_config(), i2c_config(), spi_bus_config(), LEDC, UART, ADC usage
   • main/CMakeLists.txt — REQUIRES list reveals components (mdns, driver, esp_wifi, led_strip, etc.)
   • sdkconfig.defaults — enabled features, stack sizes, Bluetooth mode
   • justfile — target chip, build variants
   • README.md / CLAUDE.md — existing hardware description
   • Kconfig.projbuild — user-configurable pin assignments

2. Identify the board from sdkconfig.defaults (CONFIG_IDF_TARGET), CLAUDE.md, or justfile. Note any board-specific constraints (e.g., ESP32-CAM PSRAM conflicts, TTGO LoRa pin reservations, ESP32-S3 USB PHY sharing).

3. Generate WIRING.md following the template below. Include ONLY sections relevant to the project — omit empty sections rather than adding placeholder text.

Template

Follow this exact structure. Every section shown is optional except Board and Pin Assignments — include a section only when the project uses it.

# <Project Name> — Wiring Guide

## Board

<Board name and variant>. Note any special constraints (PSRAM pins, onboard peripherals, USB PHY sharing).

## Pin Assignments

| GPIO | Function | Direction | Component | Notes |
|------|----------|-----------|-----------|-------|

Group related pins together (SPI bus, I2C bus, UART, etc.) with a blank row or subheading between groups.

Direction values: `Output`, `Input`, `Bidirectional`, `—` (for power/ground).

## Wiring Diagram

ASCII art showing physical connections. Keep it compact — one diagram for the whole project if possible.

ESP32

| | | GPIOx |──── Component | ... | |________|

## Components

| Component | Specification | Notes |
|-----------|--------------|-------|

Include only components that require wiring. Wireless peripherals (Bluetooth controllers, WiFi) get a one-line mention in Notes, not a table row.

## Bus Configuration

### I2C / SPI / UART

Only include if the project uses these buses. Show address, speed, or baud rate. Note any bus contention issues (e.g., shared SPI with onboard LoRa).

## Power

- Power source (USB, battery, external supply)
- Voltage rails (3.3V, 5V) and which components use each
- Current requirements (peak and typical)
- Deep sleep current if applicable
- Battery management notes if applicable

**Do not include generic ESP32 power specs** — only project-specific information.

## LED / Status Indicators

| State | Color/Pattern | Meaning |
|-------|--------------|---------|

Only include if the project has status LEDs with defined states.

## Safety Notes

Bullet list of project-specific warnings. Examples:
- Voltage level mismatches (5V component on 3.3V GPIO → needs level shifter or voltage divider)
- Components that must NOT receive 5V
- Current limits that require transistor drivers
- Pin conflicts with boot strapping

**Do not include generic electronics safety advice.**

## Troubleshooting

Only include if there are non-obvious failure modes specific to this hardware configuration.

Style Rules

• Concise over comprehensive — a 50-line WIRING.md that covers all connections beats a 300-line tutorial
• No generic content — omit GPIO reference tables, "safe pin" lists, breadboard ASCII art, expansion ideas, component substitutions, and enclosure advice unless directly relevant
• Pin numbers are authoritative — derive from source code #define values, not README prose. If they conflict, flag the discrepancy
• ASCII diagrams over Mermaid — renders everywhere without a renderer
• Decimal GPIO numbers — use GPIO4 not IO4 or Pin 4
• One table for all pins — don't split across multiple tables unless bus grouping genuinely aids readability
• Notes column — use for pull-up/down requirements, strapping pin warnings, "input-only" constraints, or alternative pin options