FWIW, tgtap does all the IP, MAC and ARP stuff for you. It will
continue searching for ip addresses and update the arp cache as new
devices appear on the network, so you don't have to worry about it
once started.
fpga.tap_start("my10gbe_core",mac_addr,ip_addr,port)
where "my10gbe_core" is the simulink name of the port you want to
configure and mac_addr, ip_addr and port (integers) are the addresses
you'd like to assign to this core.
eg ip of 10.0.0.12 = 10*2^24 + 0*2^16 + 0*2^8 + 12 = 167772172
recommended mac address is 02:01:01:xx:yy:zz where xx, yy and zz are
arbitrary (I just pick the lsbs from the IP address).
Please make sure you're running updated versions of the katcp and corr
python package, tgtap, tcpborphserver and the linux kernel if you want
to use tgtap. I will package a new recommended roach filesystem and
check it into SVN later this week with all the current versions pre-
packaged.
Jason
On 23 Mar 2010, at 11:37, Nevada Sanchez wrote:
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, [email protected] 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, [email protected] 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
