| Offset | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|---|
| 0x0000 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0008 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0010 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0018 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0020 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0028 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0030 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0038 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0040 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0048 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0050 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0058 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 0x0060 | 0 | 0 | 0 | 0 |
Online MODBUS RTU/ASCII Slave Emulator
Device addresses (click to toggle active/inactive)
How the MODBUS Emulator Works
The utility uses a special programming interface (Web Serial API) to interact with COM ports directly from the browser.
When the port is open, the program waits for requests from the master and generates the appropriate response. To stop the emulator, simply click the "Disconnect" button.
Main Advantages
The primary advantage is that there is no need to install specialized software, drivers, or third-party libraries. You can emulate a MODBUS slave device right from your browser.
Is it Safe?
Working with serial ports through a browser and the Web Serial API imposes strict restrictions to protect users. You can review the key security aspects on a separate page.
Is There an Offline Version?
Our Advanced Serial Port Monitor software includes a module for MODBUS device emulation. Additional benefits of this utility include:
- Faster response times.
- Advanced error emulation through direct port access.
- Ability to save the register map and settings to local files.
- It can work as a MODBUS master and request memory area.
- Other MODBUS-specific functions.
Which Serial Ports Can the Page Work With?
All ports successfully detected by your operating system are available for selection. The utility only accesses the specific port explicitly authorized by the user.
Are There Any Limitations in the Free Online Version?
There are no functional limitations. Only the communication channel itself can impose restrictions on the emulator's response speed.
Other MODBUS Utilities
Related topics: Advanced Serial Port Monitor
hereRS232 monitor RS232 analyzer COM Port Debug RS232 terminal Serial port sniffer Serial port spy UART monitor RS232 pinout and signals Data monitor cables.