Up to Discussions in Blackfin Processors

This Question is Answered

2 "helpful" answers available (2 pts)
7 Replies Last post: Jun 24, 2009 1:34 PM by Jiang Wu  
Thomas Ireland Contributor
Thomas Ireland
6 posts since
Jun 23, 2009
Currently Being Moderated

Jun 23, 2009 12:55 PM

sendto retruns correct bytes but nothing goes out on the wire for BF537, receive is fine

In the myThread.c attached I should see a UDP packet with data = 100 bytes on the wire. I have a cross over cable attached from the Target Board and My PC with a static address of 192.168.136.51

I am usign Wireshark to mintor the wire and setup a receiver in windows to chatch the packet, nothing ever shows up, to window, wireshark but the return byte count from the sendto  is correct.

 

Any Ideas?

Attachments:
Tags: lwip
Jiang Wu Analog Employee  
Jiang Wu
40 posts since
Apr 3, 2009
Currently Being Moderated
1. Jun 23, 2009 1:48 PM in response to: Thomas Ireland
Re: sendto retruns correct bytes but nothing goes out on the wire for BF537, receive is fine

In you code, I did not see bind() function call. Bind the socket to a port before transmitting data.

Report Abuse
Thomas Ireland Contributor
Thomas Ireland
6 posts since
Jun 23, 2009
Currently Being Moderated
2. Jun 23, 2009 1:59 PM in response to: Jiang Wu
Re: sendto returns correct bytes but nothing goes out on the wire for BF537, receive is fine

I tried the bind, bind worked and neither send or sento worked returing -1 with a 0 (zero) in the errno. The sento is supposed to do an implicit bind to the target anyway.

 

Tom

Report Abuse
Thomas Ireland Contributor
Thomas Ireland
6 posts since
Jun 23, 2009
Currently Being Moderated
3. Jun 23, 2009 2:17 PM in response to: Thomas Ireland
Re: sendto returns correct bytes but nothing goes out on the wire for BF537, receive is fine

An Update:

 

TCP functions just fine for RX/TX, UDP receive works fine. I checked the wire and there is "something" comming out on the wire but it looks like garbage. I suspect the LWIP has got the incorrect address for the DMA to the NIC for UDP sendto only, but I am not able to verify. BTW, this same code functions perfectly in Window XP and Linux.

 

Tom

Report Abuse
Jiang Wu Analog Employee  
Jiang Wu
40 posts since
Apr 3, 2009
Currently Being Moderated
4. Jun 23, 2009 2:39 PM in response to: Thomas Ireland
Re: sendto returns correct bytes but nothing goes out on the wire for BF537, receive is fine

Change the remote ip to 192.168.36.51. Please also find attached an example I just made with your code. It worked well - sendto returns 100 and wireshark sees the packets correctly.

Attachments:
Report Abuse
Thomas Ireland Contributor
Thomas Ireland
6 posts since
Jun 23, 2009
Currently Being Moderated
5. Jun 24, 2009 12:31 PM in response to: Jiang Wu
Re: sendto returns correct bytes but nothing goes out on the wire for BF537, receive is fine

Hi

I got a linksys wireless router so I could duplicat what your envirnment is for using 192.168.1.100; It did not work.

 

I am using the following:

 

ADSP-BF537 EZKIT LITE 2.2

Phytec PCM 975 with BF-537 daughter card

another

Phytec PCM 975 with BF-537 daughter card

custom hardware with BF-537 daughter card

 

All the results are the same, something is on the wire it is not recognised by with PC host () or Wireshark.

 

I am using Update 6 of the IDDE and yet I get a different size for the DXE than you do. There are lots of things that me do this and I don't beleive it is a problem as yet.

 

Maybe there is an uniinitialized register someplace, I am not aware of.

 

Tom

Report Abuse
Thomas Ireland Contributor
Thomas Ireland
6 posts since
Jun 23, 2009
Currently Being Moderated
6. Jun 24, 2009 12:41 PM in response to: Thomas Ireland
Re: sendto returns correct bytes but nothing goes out on the wire for BF537, receive is fine

We have now confirmed it is a Windows issue, when monitored in Linux the packets are being sent properly.

Will update when we find and fix the problem.

Report Abuse
Jiang Wu Analog Employee  
Jiang Wu
40 posts since
Apr 3, 2009
Currently Being Moderated
7. Jun 24, 2009 1:34 PM in response to: Thomas Ireland
Re: sendto returns correct bytes but nothing goes out on the wire for BF537, receive is fine

In my example, the remote IP is set to 192.168.1.100 which is my PC address. You need to change it to your target to make the example work.

Report Abuse

More Like This

  • Retrieving data ...