Hi, I'm seeing a werid behaviour in my FPGA code. We are looking at expanding the main DMA FIFO in our code and I wanted to run some benchmarks ont eh throughput with different data types (U8, U16, U32 U64 and so on) and I have noticed something quite unexpected. The performance of a VI (Running from the RT System) depends on whether I have the "Open FPGA Reference" running from a VI or a Bitfile. I have added a wait of 250ms before running any times operations but you can see the results of writing a 4M FIFO of U8 to the FPGA target below. This is using the exact came code after the "Open Reference". Any ideas ays to why this would be the case? It's super reproducible in my code. Shane. PS I'm using LV 2011 SP1

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FPGA DMA performance Bitfile or VI

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I would like some official stance ont his as as I see it, this is unneccessarily slowing down some code. I believe an 8-bit FXP DMA should only transfer 8 bits, not 64.

Shane.

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FPGA DMA performance Bitfile or VI

Re: FPGA DMA performance Bitfile or VI