How can greater transfer rates be achieved using the NI modbus VI's?

[PabloBernal]

I need to set a Modbus/Ethernet server publishing some of the process variables. I am using the NI Modbus library. I edited the MB Ethernet Example Slave to fit my application. I only need to publish registers. I modified the period on the Slave Demon and decreased the delays at the end of the secuences of the Slave and Master VI's. I achieved greater transfer rates but the communication started to be unstable as I increased transfer rate. My process variables are available every milisecond. Can I publish them at that rate without conusming a lot of CPU?

[unclebump]

Can you give us some more info about what you are publishing?? One register, two, three, a hundred. Modbus is usually limited to 100 registers per read or write command (maybe 125). Are the variables in consecutive order or spread all over the place?? How many devices are reading this data?? Show us some code.

One other thing, are you sending RTU or ASCII formatted data?? ASCII is twice as slow.

Message Edited by unclebump on 07-05-2006 03:51 PM