Acquire Read/Write Region - DMA FIFO

[pers.jolanta@gmail.com]

Hey,

is there any place I can check if specific target are supporting the function FIFO.Acquire Read Region (or FIFO.Acquire Write Region) ? I have cRIO-9068 with FPGA Xilinx Zynq 7020. I am trying to send images from RT taget to FPGA and process them on FPGA. But I am getting the error -63193:

NI-RIO:  (Hex 0xFFFF0927) The requested feature is not supported.

Does it mean that my target is not proper for this function or may there be another reasons?

Thank you for support!

[Terry_ALE]

That's interesting and unfortunate.  I wonder if this is because with Zynq the FPGA and RT processor are all on the same chip which could make it more challenging to get all the RIO drivers capabilities on the same chip?

My initial guess is that it could be impacted by the bus between the FPGA and RT processor (PXI, PXIe, or in this case same chip where the bus type is not known).

I did some searching and there is no such document and there really should be one.

[Michael_Strain · Accepted solution]

Acquire Read/Write Region are supported on the cRIO-9068.  The function calls are not supported when using remote sessions though (as they provide direct access to the FIFO memory, which doesn't make sense over RPC).

You are likely opening the session to the FPGA using "rio://<hostname>/RIO0", which will open the session remotely, you instead should try opening it with just "RIO0".

For the most part, all newer FPGA targets support this API, with the exception of USB and Ethernet devices.

[pers.jolanta@gmail.com]

You are right, this opening with RIO0 worked perfectly indeed!

One more question, have you got any resources/website or something where I can get more info about this remote sessions? Your solution worked, but I would love to understand it completely why is it so and what does it mean:)