smario Posted February 2, 2012 Report Posted February 2, 2012 I'm trying to establish communication between a Twido working as a master and two generic Modbus devices (PM710) working as slaves, but I have problems using the EXCHx and MSGx functions. I can only send the first message to the first Modbus device using the EXCHx function. After this, the value of MSGx.D never goes back to one and so the next message using another EXCHx function can't be sent. It keeps sending the first message and receiving an answer from the same slave over and over again. I configured it in the same way it's described in the TwidoSuite V2.0 Programming Software Online Help in the in the description of the Exchange Control Function Block (%MSGx) Transmission of Several Successive Messages. Can anyone please explain me how to Twido acts as a master and sends multiple messages to slaves? Thanks in advance. Quote
Grisha Posted March 4, 2012 Report Posted March 4, 2012 Hi smario, I did such project using TCP/IP, i did a counter that after every end of reading promotes it's value and i reset it after i read the last device. Hope its not late and i could help you, Good luck and best regards, Greg. Quote
koyeap Posted March 14, 2012 Report Posted March 14, 2012 Hi Smario, are you using the port 1 (RS485) of the twido controller? If you make the communication cable yourself did you jump the pin 5 and 6 on the minidin? can you show what is inside your exch.x ? Quote
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