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Does Kepware Support Twido PLCs?


Last Update: 11/12/2018

Kepware's Modbus TCP/IP Ethernet driver can communicate to Twido PLCs that have built-in Ethernet (like TWDLCAE40DRF) or to a TwidoPort Ethernet-to-serial gateway. If the Twido PLC doesn't have Ethernet, Kepware's Modbus RTU Serial driver can communicate to the PLC's Modbus serial port. In order to enter memory addresses into the driver without having to add "1" to addresses from the PLC programming software, uncheck the driver's Use zero based addressing option (located in the Settings tab of Device Properties). Once disabled, users can access the following:

  • To access memory Booleans (such as %M0 or %M2), enter an address like "000000" or "000002" into the driver. At least one leading zero is necessary. If only "02" is entered, the driver will pad it to "000002". Entering "2" without a leading zero is invalid. Furthermore, users must be careful not to start a memory Boolean address with 1, 3, or 4 because these are prefixes for other memory types in Kepware's Modbus drivers. Use 01, 03, or 04 instead.
  • To access register %MW0, enter address "400000" into the driver and then set the data type to Short. Doing so will match the PLC's convention of storing signed whole numbers in 16 bit registers.
  • To access a floating-point variable (such as %MF0 or %MF2), replace the %MF with a "4" and change the data type to Float. In this example, the whole address would be "400000" or "400002".
  • To access a double word (such as %MD0 or %MD2), replace the %MD with a "4" and change the data type to Long. In this example, the whole address is "400000" or "400002".
  • To access a bit within a memory word, use a period to separate a word number from a bit number (instead of the programming software's "%MW<word>:X<bit>" notation). For example, "400000.0".

Note: These PLCs do not make other register types (such as %I, %Q, %TM, and so forth) directly accessible via Modbus. Logic can be used in the PLC to transfer data between the %MW or %M, which can be accessed via Modbus and those other memory types.

Related Protocols
Modbus Ethernet