Wire Address Scan

I2C Wire Scan Application

Overview

This application scans the I2C bus for connected devices and displays their addresses using the Wire interface. It's a diagnostic utility that helps verify hardware connections and understand I2C device addressing.

Features

• Scans all valid I2C addresses (0x01 to 0x7F)
• Reports found device addresses in hexadecimal format
• Includes web server functionality for remote monitoring
• Provides network diagnostics capabilities

How It Works

The application performs the following operations:

1. System Initialization: Initializes the network stack and starts a web server on port 80
2. Network Setup: Waits for an active network connection
3. I2C Scanning: Sends ping requests to each address in the I2C address space
4. Device Detection: When a device responds with an acknowledgment (ACK), its address is recorded
5. Results Display: Outputs all found device addresses to the console

I2C Address Scanning Process

The scan covers addresses 1 through 127 (0x01 to 0x7F) in the 7-bit I2C address space. For each address, the application:

• Sends a request using Wire.ping(address)
• Waits for an acknowledgment from the device
• Records the address if a response is received

Output Format

For example, the application outputs scan results in the following format:

Doing scan
I2C Devices[01,48,68]
Scan done found 3 devices

Where:

• Device addresses are displayed in hexadecimal format
• Multiple addresses are comma-separated
• Total count of found devices is reported

Use Cases

This utility is particularly helpful for:

• Hardware Verification: Confirming that I2C devices are properly connected and powered
• Address Discovery: Identifying the actual addresses of connected I2C devices
• Troubleshooting: Diagnosing I2C communication issues
• Documentation: Understanding device addressing schemes in datasheets

Technical Notes

Address Format

Some I2C device datasheets include the read/write bit as part of the address specification, while others do not. This scanner reports the base 7-bit address without the read/write bit.

Address Range

• Valid Range: 0x01 to 0x7F (1 to 127 decimal)
• Reserved Addresses: 0x00 and addresses above 0x7F are not scanned as they are reserved or invalid

Network Features

The application includes network capabilities:

• Web server running on port 80
• System diagnostics enabled
• Network connection monitoring

Dependencies

• NNDK (NetBurner Network Development Kit)
• Wire library for I2C communication
• System libraries for network and timing functions

Building and Running

1. Compile the application using the NNDK toolchain
2. Flash to your NetBurner device
3. Connect to the device console to view scan results
4. Optionally access the web interface for remote monitoring

Example Output

Web Application: I2C Wire Scan
NNDK Revision: [version]
Doing scan
I2C Devices[20,3C,50]
Scan done found 3 devices

This example shows three I2C devices found at addresses 0x20, 0x3C, and 0x50.

Troubleshooting

If no devices are found:

• Check I2C wiring (SDA, SCL, power, ground)
• Verify pull-up resistors on SDA and SCL lines
• Confirm device power supply voltages
• Check for proper ground connections
• Verify device addresses in datasheets

File Structure

• main.cpp: Main application source code
• Web interface files (auto-generated by NNDK)