iautomate Posted December 14, 2010 Report Share Posted December 14, 2010 Gents, I have an application developed in a V570. I have basic Modbus TCP comms up and running. I am able to remotely monitor and control all 'MI' points in my program but I am having trouble getting any 'MB's to work at all. I have used the help doc to calculate the external MB offset. (Can be found at: Communications\Communication FBs\Modbus IP\Read Imputs then click the link to 'Slave Address Tables') This should be simple as the offset is quite simply 30001 + MB Addr. For example I am trying to monitor MB3107 wich maps to 33108 as an external MB addr. However this entire range is dead when monitoring from my Modbus OPC server. At least this is the way I understand it from the doc. I am also having the same problem with reading O and I directly. Any help would be much appreciated. Quote Link to comment Share on other sites More sharing options...
Ofir Posted December 21, 2010 Report Share Posted December 21, 2010 Hi, Please note that there are 2 slave address tables, one for standard vision and one for enhanced vision. You need to use the Enhanced slave address table - please note that the addresses are in HEX. For reading coils i assume that the address will be 10001 + offset - Can you try it? Quote Link to comment Share on other sites More sharing options...
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