Hi Heystek, Gonna throw this one to the maillist because some other folk might find the conversation useful.
Am I right in thinking that you have a ROACH2 design which is outputting data over the 10GbE port (similar to the transmission side of tutorial 2) but want to know how to receive the data from a server, rather than just the loopback test performed in the tutorial? If so, the answer is, you'll need some code similar to https://wiki.python.org/moin/UdpCommunication#Receiving This will work fine for relatively low speed - for higher performance you'll probably want to look at using the C socket library directly, or one of the various higher-level libraries that other astronomy folk use which include (e.g. spead2 (for reading SPEAD packets) and/od full piplineing engines like HASHPIPE / Bifrost). Needless to say, everyone likes their software to be slightly different to everyone else's, so there are a bunch of libraries around. But I'd recommend starting with python to get the hang of things. In the example, you instantiate a UDP/IP socket (the traffic from a CASPER 10GbE core is always UDP), and bind it to the IP address and port you want to receive on (i.e, this should be the same as the destination address the ROACH is using). Then you simply call recvfrom (or recv) against the socket and get your data back as a raw binary string (which you'll need to decode with struct.unpack calls (or numpy.fromstring, or similar). Things you might want to try when this inevitably doesn't work out the box. 1. Verify your ROACH really is sending packets by putting some registers which count the number of valid eof pulses going into the ethernet core. (some of this kind of debugging is automatically built in to casperfpga -- see tut2 for details) 2. run tcpdump (`sudo tcpdump -i <interface name (e.g. eth1)>`) to verify that packets are showing up at your machine. Use tcpdump's -e flag to check that the MAC addresses / IP addresses in this packet are what you expect. 3. Write a simple python TX script ( https://wiki.python.org/moin/UdpCommunication#Sending) to send packets from one server to another, to verify your receive code is working without the bazillion unknowns a ROACH brings to the table. 4. Be sure to check that the packets you are sending are smaller than the MTU ( https://www.cyberciti.biz/faq/how-can-i-setup-the-mtu-for-my-network-interface/) that your server will accept Cheers Jack On Tue, 8 Oct 2019 at 03:08, Heystek Grobler <[email protected]> wrote: > Hey Jack > > I hope that you are still doing well? > > I am struggling with the 10GBE SFP+ block. I have it in my design, the > design complies and is working, but how do I actually get the data from > the 10 GBE block? > > To use a python script with a BRAM block over normal ethernet is easy, but > how do I go to work with the 10 GBE block? The tutorials do not really > explain it or provide an example. > > Have a great day > > Heystek > > > -- > Heystek Grobler > 0832721009 > 012 3013202 > [email protected] > > Spectroscopy Research Group > Department of Fundamental Astronomy > South African Radio Astronomy Observatory (SARAO) Hartebeesthoek Site > > > -- You received this message because you are subscribed to the Google Groups "[email protected]" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/a/lists.berkeley.edu/d/msgid/casper/CAG1GKSnwU6og5vDkWJOa%2BOkpM5bN4Rr7W6NYTSLN%3DyzG6--6zw%40mail.gmail.com.
