To initiate a read request from the device, select the device's window and do one of the following:
Select Read Registers from the Messages menu.
Click thebutton on the toolbar.
The Read Registers dialog box opens.
To specify the request:
Enter the polling interval in the Polling Interval field.
Enter the starting Holding Registers memory address where you want to read data in the Starting 4X Register field.
Enter the number of registers to read in the Number of registers to read field.
When the request completes, the window for the device looks like this:
Step 3. Test Communication.