FPGA 8.5 cluster problem

[leonlobo]

I created a cluster of four boolean controls in LV FPGA 8.5 and then compiled it. In LV8.5 PDS though why does selecting 'All Elements' in FPGA's read/write control create a write type but selecting the components of the cluster create a read type?

[Ian Colman]

Hi,

This is expected behaviour. The real time code interfaces with the FPGA in memory blocks as this is the most efficient way of interfacing. This is why you can pass a whole cluster into your read/write node, and read a whole cluster from it.

For the same reason you cannot pass an individual cluster element into the FPGA target VI. You have to bundle your new cluster together and pass the whole thing in. The reason you can read a cluster element directly from the node is because the node unbundles the cluster for you, after it has read the cluster from the FPGA as a whole.

Hope this helps,

Ian C.
Applications Engineer
National Instruments