Re: [casper] bram and katcp

Hello I'm also going to look at another option which is with the mmap kernel I have access to the FPGA memory in /dev/roach/mem. I think it should be fairly easy to write a custom server that runs on the roach that collects the bram data from the mem and then buffers if for sending over

Re: [casper] bram and katcp

If you do large reads (ie single request), I've managed 8Mbps using KATCP. Our RATTY1 design does 16384x64b channels every 500ms, which is 2Mbps. The key is to do lots of big reads rather than lots of little ones. However, I would stress that the KATCP path is designed for control and

Re: [casper] bram and katcp

Hello The path FGA-PPC-ethernet-python hasn't been optimised for speed. So if you can get hold of a PCI(e) CX4 ethernet card for your capture machine then you will save yourself a considerable amount of effort and get way better max transfer rates However: If this isn't an option, there are a

Re: [casper] bram and katcp

Thanks everyone for the input. I've been trying not to move towards the 10 gb option if possible for a couple of reasons but I might have to bite the bullet. I'm also going to look at another option which is with the mmap kernel I have access to the FPGA memory in /dev/roach/mem. I think it

Re: [casper] bram and katcp

Hi Dave, Boot the board, stop in U-Boot, write to the DMA registers directly, and probe the bus to see what the maximum rate possible is ... then you can decide whether to write a device driver to use the DMA controller under Linux. Oh, yeah, trying to use the DMA controllers on the PPC side

Re: [casper] bram and katcp

Hi Guys, Thanks - I'm initially going to pursue the mmap option. I think quite a few of the issues are tcp latencies and by removing those I can make the link more reliable. I'm looking at a max of about 5Mb/s through the FPGA--PPC interface. I should fairly soon be able to check what speed I

Re: [casper] bram and katcp

So I just did a very quick test where I read 10 an ADC snapshot (8192 Bytes) via mmap(boost::iostreams::mapped_file) using std::copy(). This took about 52 seconds which is about 15MB/s or 120Mb/s - Sound to fast??? Ross On Wed, Oct 16, 2013 at 11:47 AM, Ross Williamson

[casper] bram and katcp

I was wondering what kind of readout speed should I expect through katcp (python) and the tcpborphserver3 on a Roach1 (MMAP). My simple spectrometer design has 16/channels per fft (48_34 bit) with 8 simultaneous paths (total of 128 channels). These get fed into 12 brams (32 bits 2^10 address).