Hi Nevada, Thanks for the input. But I haven't yet figured out what's wrong. I tried setting the source_ip directly as you suggested, but this had no effect. And in any event, the source_ip, destination_ip, and port as indicated by Wireshark are all correct (as I set them). It's just that my python client doesn't read any data.
Also, I updated my ROACH board just last week according to http://www.mail-archive.com/casper@lists.berkeley.edu/msg01058.html. With one difference, I used the kernel uImage-jiffy-20091110. Anyway, I'll update at the end of the week as Jason suggests. But it'd be nice to figure this out before then. Sean > We've had similar problems before. If you're going to use sockets, you > need to be sure that you are setting the source IP address on the GBE > module. Otherwise, you will see packets in Wireshark, but not in the > sockets. You can do this in python with something like > > fpga.write(gbe_block, source_ip, offset = 0x10) > > (Here gbe_block is the name of the gbe yellow block). Also, it might be a > good idea to set an arp entry on the roach, with something like the > following: > > > def set_arp_entry(dev_name, last_ip_octet, mac): > assert(last_ip_octet < 256) > fpga.write(dev_name, mac, offset = 0x3002 + last_ip_octet*8) > ... > set_arp_entry(gbe_block, 1, pc_mac_addr) > > > You will not get very high data rates through Python (it's too slow). I > would suggest using similar code, but in C. > > -Nevada > > On Mar 23, 2010, at 14:21 PM, mch...@physics.ucsb.edu wrote: > >> Hi Paul, >> >> Thanks for the reply. By "not working" I meant that no data appears and >> therefore the script stalls on the line >> data = s.recvfrom(1024)[0] >> >> Also, currently I don't need very high data rates (~ 10Mb/s), but I will >> need them in the near future. >> >> >> Sean >> >>> Hi Sean, >>> >>> I've used python code almost identical to yours pretty successfully, >>> mainly for simple tests/debugging. Whether or not this is the right >>> way >>> to build a bigger application depends on things like the data rate you >>> need to support, any additional data processing/formatting that needs >>> to >>> be done, etc. >>> >>> What form of "not working" are you experiencing? ie, an error message, >>> no >>> data appears, data comes in but you can't keep up with it... or >>> something >>> else? >>> >>> -Paul >>> >>> On Tue, 23 Mar 2010, mch...@physics.ucsb.edu wrote: >>> >>>> Hi all, >>>> >>>> I need to dump data from a ROACH board to a PC over the 10gbe. Do any >>>> of >>>> you have any recommendations for what I should use as a client to >>>> handle >>>> the incoming data? >>>> >>>> I've been trying to use a simple Python client like, >>>> >>>> s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) >>>> s.bind((ip_address, port)) >>>> data = s.recvfrom(1024)[0] >>>> >>>> where "ip_address" is the address of the pc's 10gbe nic. This has >>>> worked... only occasionally. And I'm not sure why it fails. Using >>>> Wireshark I can see the incoming packets are coming in with 1024 bytes >>>> from the ROACH as I expect. Any thoughts? >>>> >>>> Thanks a lot. >>>> >>>> >>>> Sean >>> >> >> >> > > >
