logicmso

Saleae Logic MSO Analysis

This skill enables analysis of captured signals from Saleae Logic MSO devices using the saleae-mso-api Python library. It supports loading binary exports, analyzing signal transitions, and decoding common protocols.

Prerequisites

• saleae-mso-api Python package — Do NOT blindly pip install. First check if it's already installed:

  python3 -c "from saleae.mso_api.binary_files import read_file; print('saleae-mso-api is available')"
  

  Only if that fails, install it: pip install saleae-mso-api
• Binary export files from Saleae Logic software (.bin format)

Quick Reference

Loading Binary Files

from saleae.mso_api.binary_files import read_file
from pathlib import Path

file_path = Path("capture.bin")
saleae_file = read_file(file_path)

# Access metadata
print(f"Version: {saleae_file.version}")
print(f"Type: {saleae_file.type}")

# Access data
contents = saleae_file.contents

Digital Capture Structure

Digital exports contain DigitalExport_V1 with chunks:

chunk = saleae_file.contents.chunks[0]

# Key attributes:
chunk.initial_state      # Starting logic level (0 or 1)
chunk.transition_times   # numpy array of transition timestamps (seconds)
chunk.sample_rate        # Capture rate in Hz
chunk.begin_time         # Capture start time
chunk.end_time           # Capture end time

Calculating Pulse Durations

import numpy as np

times = np.array(chunk.transition_times)
durations_ms = np.diff(times) * 1000  # Convert to milliseconds

# If initial_state is 0 (LOW):
#   - Even indices (0, 2, 4...) = HIGH pulse durations
#   - Odd indices (1, 3, 5...) = LOW gap durations
# If initial_state is 1 (HIGH):
#   - Even indices = LOW gap durations
#   - Odd indices = HIGH pulse durations

Helper Scripts

This skill includes helper scripts for common analysis tasks:

Protocol Analyzer

# Analyze signal characteristics
python3 skills/logicmso/analyze_protocol.py capture.bin

# Show detailed timing histogram
python3 skills/logicmso/analyze_protocol.py capture.bin --histogram

# Show detected timing clusters
python3 skills/logicmso/analyze_protocol.py capture.bin --clusters

# Export transitions to CSV
python3 skills/logicmso/analyze_protocol.py capture.bin --export transitions.csv

# Show raw transition values
python3 skills/logicmso/analyze_protocol.py capture.bin --raw -n 50