Hi,
I'm looking to control the PXI-Profibus card using NI-VISA. I'm building a simulation environment using the PXI chassis to simulate the end system devices that our control system interfaces with. There many PB slaves. Also, there are different versions of the end system where will need to reconfigure the PXI hardware. As an example, one of my goals would be to have the ability to programmatically set the slave address for each profibus card based on data from a database.
So far from a previous post and reading the VISA manuals, I have the understanding that I will need to control the profibus card by using PXI::INSTR and that a sample resource name will be PXI::2::INSTR. Basically I'm trying to implement what the ComSoft product does since I learned that is uses VISA.
From the VISA user manual, do I need to use Message-Based comms or Register-Based comms? If it will be Register-Based, what is the memory map of the registers, I/O buffers, etc and a description to go along?
Reading up on the Profibus protocol, I see that only OSI layers 1,2 and 7 are used. Does VISA or the PXI-Profibus card take care of Layer 2? How much of the Profibus packet has to be built at Layer 7 before writing to an output buffer?
Any help would be much appreciated.
Omar
