# LED GPIO Utilities

This directory contains utility talking to RTL837x switch IC via I2C bus. These scripts are designed to help with monitoring, debugging GPIO, and identifying LED configurations.

## Hardware requirements

To use these utilities, you need:

  - A hardware dongle that can communicate with I2C devices. One example is the [I2C-Pico-USB](https://github.com/dquadros/I2C-Pico-USB) which provides USB-to-I2C connectivity.
  - Connection between the hardware dongle and the RTL837x's I2C communication port.

## Scripts

### 1. `i2c_read_rtl_gpio.py`

This script reads RTL GPIO register values via I2C and displays changes in GPIO states.

**Features:**

  - Reads live RTL GPIO register values via I2C (default address 0x5C)
  - Monitors GPIO changes with delta detection
  - Allows specification of I2C bus, sleep interval, and ignored GPIO pins
  - Shows changes in real-time with GPIO index display

**Usage:**
```bash
# Basic usage (defaults to I2C bus 1, 2s sleep interval)
python3 i2c_read_rtl_gpio.py

# Specify I2C bus
python3 i2c_read_rtl_gpio.py --i2c-bus 0

# Specify sleep interval in seconds
python3 i2c_read_rtl_gpio.py --sleep-interval 5

# Ignore specific GPIO pins
python3 i2c_read_rtl_gpio.py --ignored-ios 28 31 34 44

# Combine options
python3 i2c_read_rtl_gpio.py --i2c-bus 2 --sleep-interval 1 --ignored-ios 28 31
```

**Output Format:**

  - Displays register address and data in hex format
  - Shows GPIO pins that have changed since last read
  - Example: `0044: 00 00 00 00 00 00 00 00`

### 2. `i2c_dump_rtl_regs.py`

This script dumps all register values from an RTL device via I2C.

**Features:**

  - Dumps registers sequentially from address 0x0000 to 0xFFFF
  - Reads 16 bytes at a time for efficiency
  - Configurable I2C bus number
  - Provides complete register dump in hex format

**Usage:**
```bash
# Basic usage (defaults to I2C bus 1)
python3 i2c_dump_rtl_regs.py >reg_dump.txt

# Specify I2C bus
python3 i2c_dump_rtl_regs.py --bus 0 >reg_dump.txt

# Or using short option
python3 i2c_dump_rtl_regs.py -b 2 >reg_dump.txt
```

**Output Format:**

  - Displays address and 16 bytes of data in hex format
  - Example: `0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00`

### 3. `dec_leds_from_dump.py`

This script decodes LED configuration from a register dump file ( the output from `i2c_dump_rtl_regs.py`).

**Features:**

  - Parses register dump files (reg_dump.txt format)
  - Decodes LED pad configurations and LED sets
  - Maps LED types to bit positions based on configuration
  - Outputs LED mux configuration and set mappings

**Usage:**
```bash
# Must be run in same directory as reg_dump.txt
python3 dec_leds_from_dump.py
```

**Output Format:**

  - LED pad configuration (hex values for each pad)
  - LED set configurations with descriptions of LED types
  - Port selection mappings

**Requirements:**

  - Requires a `reg_dump.txt` file containing the register dump output

## Requirements

All scripts require:

  - Python 3
  - `smbus2` Python package

Install with:
```bash
pip3 install smbus2
```

## Common Usage Patterns

### Monitoring GPIO Changes
```bash
# Monitor GPIO changes on bus 1 with 1-second intervals
python3 i2c_read_rtl_gpio.py --i2c-bus 1 --sleep-interval 1
```

### Register Analysis
```bash
# Dump all device registers
python3 i2c_dump_rtl_regs.py --bus 2 > reg_dump.txt

# Analyze the register dump to understand LED configuration
python3 dec_leds_from_dump.py
```

## Configuration

All scripts support command-line arguments for flexible configuration:

  - `--i2c-bus` or `-b`: Specify I2C bus (default: 1)
  - `--sleep-interval` or `-s`: Sleep between reads in seconds (default: 2)
  - `--ignored-ios` or `-i`: GPIO pins to ignore (default: [28, 31, 34, 44])