Can Citect Scada software communicate with Twido controller from Schneider using Modbus? How with addressing?

 

The Schneider web site says that the Twido can communicate using Modbus RTU or Modbus ASCII. Based on this Citect can definitely communicate with this controller. This device does not appear in out list of devices in the 'Express Communications Wizard' but if you tell it you are going to talk to a Modicon 948 controller using ASCII or Binary comms this will work fine. (The I/O subsystem doesn't really know about devices, it only knows about protocols. The wizard is just there to speed things up and to help out people who don't know what protocols a device supports)

As for the address / memory mapping of this controller I don't know.

Hope this helps.

Kelvin

Disclaimer: I am an employee of Citect Pty. Ltd. This should not be
considered an authorised communication from Citect. For official support information please contact Citect Support. See http://www.citect.com
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Yes!

In the Modbus the holding area (4x) are in the Twido %Mw. The Coil area in the Modbus (0x) in the Twido %m.
One remark: you must shift the address!

%mw0 -> 400001
%mw1 -> 400002
%m0 -> 000001

 

Citect can communicate with Modbus devices via drivers supplied standard with Citect. They have ASCII and RTU drivers. Addressing is standard Modbus.

Check at http://www.modbus.org. Schneider sponsor this forum. There is a link to the Modbus discussion forum at the top of the page.

 

Twido uses IEC notation where the first of anything (register, input, output, etc.) is number zero - whereas in MODBUS that assumes a classic MODICON PLC, the first of anything is number one. Bottom line, mentioning 40001 to the driver will get your the first Twido register (or Memory word as called in IEC lingo).

Meir

 

How about address %MW507:X11 in Twido (Modbus TCP)?

 

Normally 40508.5 is the address in Citect!
Of You set in the citect.ini: [MODNET]RegisterBitReverse then 40508.11!

Best regards!
Zsolt