v1.2.0 - Four-Point Probe, Modular Architecture, and Enhanced UI

🎉 What's New in v1.2.0

This release brings major architectural improvements, a powerful new measurement mode, and significant UI enhancements.

🚀 Major Features

Four-Point Probe (4PP) Measurement Mode

• Complete 4-point probe measurement system with configurable probe geometry
• Real-time sheet resistance (Rs), resistivity (ρ), and conductivity (σ) calculations
• Support for thin film and bulk models with customizable correction factors
• Advanced options: custom K factor, alpha multiplier, thickness input (µm)
• Live statistics display (mean, std, RSD) with measurement table
• Summary export with averaged results
• Remote sense (RSEN ON) enabled automatically

Modular Codebase Architecture

• Breaking structure change: Refactored monolithic script into resistamet_gui package
• Organized into logical modules: constants, config, buffers, workers, instrument, ui/
• Improved maintainability and testability
• Entry point preserved for backward compatibility

Instrument Abstraction & Profiles System

• New Keithley2400 VISA wrapper for cleaner instrument communication
• Profiles: Save and load measurement configurations per mode (JSON format)
• Quick GPIB selection popup on connection errors
• Global compliance-stop setting across all modes

Results Viewer

• New built-in CSV viewer tab for analyzing past measurements
• Plot any column from exported data
• Integrated into main window for easy access

🎨 UI/UX Enhancements

Improved Layout System

• QSplitter integration for resizable panels (Parameters, Plot, Controls, Status Log)
• View menu toggles to hide/show sections and maximize plot area
• 4PP horizontal layout: Parameters on left, Summary/Table on right for optimal screen usage
• Windows compatibility fixes for zero-size widget rendering

Enhanced Controls

• Pause/Resume functionality across all measurement modes
• Event marking (M key shortcut) during measurements
• Per-mode plot variable selectors (voltage, current, resistance)
• Dynamic axis labels that update with plot variable selection
• Plot visibility toggle (useful for 4PP when only data is needed)

🔧 Improvements

Instrument Limits Updated

• Voltage range: -100V/+100V → -200V/+200V (enables negative bias)
• Current range: ±1A → ±3A (full Keithley 2450 capabilities)
• Fixed input restriction preventing entry of 100V or values >1A
• Applied across all measurement modes

Data Handling

• Enhanced EnhancedDataBuffer with multi-channel logging
• UTF-8 BOM in CSV exports for proper special character support (Ω, µ)
• Fixed thickness unit migration (legacy cm → modern µm)
• Improved timestamp formatting and event tracking

🐛 Bug Fixes

Four-Point Probe Specific

• Fixed summary stats and table not resetting between measurements (b32e401)
• Eliminated divide-by-zero warnings in export and data processing (a74ee52)
• Fixed VOLT,CURR reading parsing and duplicate compliance logic (72e210c)
• Resolved buffer KeyError for four_point mode (b6483f1)
• Fixed model info updater Qt signal handling (1033d07, d3bd033)

UI/Plotting

• Prevented Matplotlib "Configure Subplots" toolbar crash (143e6b2)
• Fixed duplicate Results Viewer tabs (baa8588, fa018b3)
• Resolved import errors for QTableWidget/QDialog (660a409)
• Fixed control enable/disable for four_point mode (e2728e3)

Windows Compatibility

• Robust handling of zero-size splits on Windows (8c3d362)
• Safe split pane initialization with sensible defaults (e0208c7)

📦 Maintenance

• Updated .gitignore to exclude macOS system files (.DS_Store)
• Removed old documentation and deprecated code from version control
• Improved code organization and separation of concerns

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📥 Installation

pip install -r requirements.txt
python resistamet-gui.py

🔗 Full Changelog

26 commits since v1.1.0: v1.1.0...v1.2.0

🙏 Notes

• Settings and profiles are backward compatible
• Existing measurement data can be opened in the new Results Viewer
• The modular structure maintains the same entry point (resistamet-gui.py)

v1.1.0

Addition of voltage and current application

Full Changelog: v1.0.0...v1.1.0

1.0.0

This is the initial software release.

Full Changelog: https://github.com/PEEKPerformer/ResistaMet-GUI/commits/v1.0.0