When entry is entered with serial port name of "COM1", "COM2", or subsequent serial port number, the properties will be made available for serial port configuration automatically. On the other hand, Modbus TCP/IP device shall be entered with its IP address with port number like "192.168.1.1:502". Note that the trailing ":502" is the standard Ethernet port number for Modbus, it should be the same in most Modbus devices.
Other than the serial communication properties, the essential configurations are the same for both type of devices. Information for each properties item is displayed at the right bottom when each item is clicked or being configured.
- Device - Address offset
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Adjust the address forward or backward if it is mismatched between SCADA and device.
- Device - Write retry
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Number of retrial upon write error/timeout.
- Device - Address increment for 32 bit data
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This setting is applipable for Floating point or Long integer data. Some devices like Schneider PLC's 32 bit data constitute of 2 addresses, so the address for floating point data listing will appear to be skipped with either odd numbers or even numbers. In such case, this setting needs to set to value of 2.
- Device - Address increment for 64 bit data
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This setting is applipable for Floating point or Long integer data. Some devices' 64 bit data constitute of 4 addresses, so the address for floating point data listing shall be incremental by 4. In such case, this setting needs to set to value of 4.
- Data arrangement - 2 bytes (16 bit)
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Some device may have an integer data swapped. This setting shall allow little endian or big endian data convention.
- Data arrangement - 1 byte (8 bit)
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This setting shall allow little endian or big endian data convention.
- Data arrangement - 4 bytes (32 bit)
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This setting is more often need to change as compare to the rest of the data byte size, as it's meant for commonly used float 32 or long 32 data, in performing data swapped display. Normally the setting shall be "2143" or "4321".
- Data arrangement - 8 bytes (64 bit)
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This setting allows double 64 or long 64 byte swapping just like the rest of the different length data.