Copy and paste your exactly as provided in your purchase email. Click OK . ⚠️ Important Security Note
| Software | Pros | Cons | | :--- | :--- | :--- | | | Free for up to 30 registers; no time limit. | Limited data points; fewer display options. | | QModMaster | Open source; supports RTU/TCP; cross-platform. | Basic UI; occasional stability issues. | | Simply Modbus | Free 14-day trial; clear interface. | Trial expires completely vs. Modbus Poll’s 30-min limit. | | pyModbus (scripting) | Unlimited and free; total control. | Requires Python programming; no GUI. |
: Use features like Traffic Monitoring, Address Scanning, and Real-time Charting for deep network analysis. Modbus Poll User Manual
: The software offers a 30-day trial . During this period, the program will run for 10 minutes at a time before requiring a restart.
Some forums suggest turning back your system clock or blocking the software’s internet access. This does not reset the 30-minute timer—the software uses a local monotonic counter. It also breaks other Windows functions.