Modbus Connect v0.6.0: IP Range Scanning
Scan entire subnets for Modbus devices with two speed modes, CIDR notation support, and smarter discovery.
What's New in v0.6.0
- IP range scanning with quiet and fast scan modes
- CIDR shortcut support (e.g.
192.168.1.0/24) - Concurrent Modbus discovery in fast mode for faster subnet scans
- Scan duration estimation and unresponsive IP logging
- Multiple scanner fixes for quiet mode timeouts and IP classification
IP Range Scanning
The Device Scanner now supports scanning entire IP ranges for Modbus devices. Choose between two scan speed modes depending on your network environment and requirements.
Quiet Mode (Default)
Sequential Modbus discovery on each IP without TCP pre-scan. The traffic is indistinguishable from normal Modbus communication — ideal for production networks where you don't want to trigger any security alerts.
Fast Mode
Concurrent TCP port scan with configurable concurrency, followed by Modbus discovery only on responsive IPs. Responsive IPs are probed in parallel for significantly faster subnet scans. A warning dialog appears on first use (dismissable with "Don't show again").
Scanner UX Improvements
CIDR Shortcuts: Type 192.168.1.0/24 to auto-fill start and end IP addresses and switch to range mode automatically.
Scan Estimation: Duration estimation displayed inline, with a warning dialog for scans estimated over 10 minutes.
Advanced Settings: Collapsible panel for fast mode configuration — concurrent connections and TCP scan timeout.
Unresponsive IPs Log: Collapsible log showing failed IPs with reason and timestamp after range scans.
Per-Device IP Display: Device cards now show the IP address for each device found during range scans.
Fixes
Quiet Mode Timeout: Fixed quiet mode scan ignoring timeout settings — each unreachable IP was attempted 3 times with full timeout. Now a single TCP connectivity check gates Modbus probing.
IP Classification: Fixed Modbus-reachable IPs incorrectly appearing in the "Reachable IPs — No Modbus" list, and quiet mode misclassifying unreachable IPs as reachable.
ICMP Ping Sweep: Added ping sweep for TCP-unresponsive IPs — pingable hosts without port 502 now appear in the "Reachable IPs — No Modbus" section.
Fast Mode Timeout: TCP scan now uses the user-configured timeout instead of a hardcoded 500ms cap.
Download v0.6.0 Today
Modbus Connect v0.6.0 is available now as a free download for Windows, macOS, and Linux.
Recommended for All Users
This release adds powerful network scanning capabilities. We recommend all users upgrade to v0.6.0.
Download v0.6.0Recent Blog Posts
Modbus Connect v0.5.0: Session Labels & Stability
Custom session labels, chart improvements, and critical stability fixes for extended monitoring sessions.
Milestone: Our First User Outreach & A Critical Fix
A major milestone for Modbus Connect with first user feedback and a critical fix for 32-bit Float data handling.
Modbus Connect v0.4.0: Complete UI Redesign
A ground-up redesign with modern dark theme, improved navigation, and keyboard shortcuts.