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Capture Your First Trace

This guide will walk you through capturing and analyzing your first digital signal with OpenTraceLab.

Hardware Requirements

You'll need a logic analyzer to capture digital signals. OpenTraceLab supports many devices, but the most common and affordable option is: - FX2-based logic analyzers - Available for ~$10 by searching for "24MHz Logic Analyzer" - Quality probe hooks - E-Z-Hook XKM series recommended

Step 1: Connect Your Hardware

  1. Connect your logic analyzer to your computer via USB
  2. Attach probe hooks to the signals you want to analyze
  3. For this example, we'll analyze I²C signals (SCL and SDA lines)

Step 2: Capture Signals

Launch OpenTraceView and: 1. Select your logic analyzer device 2. Configure the sample rate (e.g., 1MHz for I²C) 3. Set up channel labels (SCL, SDA) 4. Click "Run" to start capturing Signal capture

Step 3: Add Protocol Decoders

Once you have captured data: 1. Go to Decoders menu 2. Select I²C decoder 3. OpenTraceView will automatically map SCL/SDA channels 4. View the decoded I²C messages I²C decoding

Step 4: Stack Decoders (Advanced)

For chip-specific analysis: 1. Go to Stack Decoder menu 2. Select a device-specific decoder (e.g., DS1307 RTC) 3. View human-readable command interpretations Stacked decoder

Command Line Analysis

Use OpenTraceCLI for automated analysis: 

# Basic capture
OpenTraceCLI --driver=fx2lafw --config samplerate=1M
# Live I²C decoding
OpenTraceCLI --driver=fx2lafw --config samplerate=1M --continuous -P i2c:scl=0:sda=1
# UART decoding with custom settings
OpenTraceCLI -d fx2lafw -c samplerate=250000 -P uart:rx=D0:baudrate=9600 -A uart=rx_data

Next Steps