uNetwork receive

[intern]

Hi

I am trying to communicate between two boards with uNetwork.
One of the boards transmit, while i look at the other with debugger with breakpoints.
The transmitter board i have setup, but i am not sure how to set the other up. I have used the documentation for uNetwork.

i am using single address and i don't know how i can see that a board have received something from the other board and how i can see on the board sending that the data was not received.

I use wireshark to see the communication, CW10.2.

Which function is called when a frame is received?



Regards

The Newbie

[mark]

Hi

The first thing to do is to watch the uNetwork frames being sent using Wireshark. If you are sending broadcast frames there will be just one transmission but if you are sending to a specific destination you should should see some repetitions, assuming that the receiver is not responding to them. If the receiver is correctly receiving it wil acknowledge them.

Check that the destination MAC adress corresponds to the MAC address of the destination card and correct it if not since the destination will otherwise not receive it.

Also check the protocol being used - both nodes should be using the same value.

Any Ethernet receptions to the correct MAC address aand with the correct Ethernet protocol (uNetwork value) will pass through the routine
extern void fnHandle_unet(unsigned char *ucData)

Therefore you can first set a break point in here at the receiver and it should be hit each time a uNetwork frame is received.

Regards

Mark

[intern]

Thanks..

Now i just have another problem.

I have these two boards. The transmitter board sends to the receiver board and the receiver board ACk it. That is what i see in wireshark.
My problem occur when the transmitter board needs to send a second frame to the receiver board, in my code i can see it calls the function and gets though it as nothing is wrong, but if i look in wireshark nothing happens.
If i restarts both boards it does the same thing.
If the receiver board isn't connected, the transmitter board sends it a lot of times.

Hope you can help me..

[mark]

Hi

You will need to see what fnDistributedTx() is doing. It works once and it is also possible to send additional messages before the first one is acknowledged (up to the limit of queued messages defined by MAX_STORED_MESSAGES).

There are several reasons why there may be no transmissions:
- first of all, if you send to a task that is local (and not remove) it will simply deliver locally and you won't see anything
- then, there are a few reasons why the routine would not send (see the return 0 cases in it)
-- like invalid destination node, invalid destination MAC address, which could be configuration errors
-- also check that the length of the data sent is not greater than MAX_UPROT_MSG_SIZE

What happens if you send exactly the same message more than once - this should each time be sent identially.

Regards

Mark

[intern]

Hi

I am trying to send the same message again and again, but after it have send the first and received an acknowledge it can't send to the same MAC-address. If i try to send the same message twice to the same MAC-address it only sends the first if it gets an acknowledge, if i then try to send global or to another MAC-address it those that fine.
The communication is between to boards on the local LAN network.

For the two boards to communicate again i need to restart both boards.

[intern]

The attached file shows what i see in Wireshark when i try to send four messages to '02' from '01'. i am trying to send them more than ones, but as you can see they only appears  ones

This is the code where the function is called.

Code: [Select]

if(count1 == 3){
fnSendMessageG(102,2);       
fnSendMessageG(102,2);
fnSendMessageG(90,2);
fnSendMessageG(40,2);

count2++;
}
if(count1 == 5){
count1 = 0;
}The function is made from the documentation for uNetwork for single address.

I have looked at the 'return 0' in uNetwork.c, i have also gone though fnDistributedTx() in debugging mode but can't see anything wrong in it..

[mark]

Hi

Your code shows that you send 4 message immediately after another. The image from your Wireshark recording shows 4 Ethernet frames being sent from MAC 00-00-00-00-00-01 to MAC 00-00-00-00-00-02 and 4 acknowledgements being returned from MAC 00-00-00-00-00-02. This all takes place quickly, with all 4 messages being acknowledged within about 300us.

When you write that they only appear once do you mean that all 4 only appear once?

From the code that you show it is not clear that they are sent more than once - will all 4 be sent periodically? If so, how often?

Since this shows 4 messages being sent to the same MAC address, could you explain why you write that you can send only 1 to a particular MAC address?

At the moment the recording matches up with the code that you have shown.

Regards

Mark

P.S. It may be better to upload Wireshark recordings as *.pcap files since it is then possible to also see the data and any other details that could be useful when analysing them.

[intern]

Hi

yes i mean that it only are the 4 that appears once(wireshark 01-02).
In the code it comes into this 'if' every 10 sec, but i only get these 4.
I can only write once because if the messages isn't send right after each other they never gets send.

The problem is more visible when i use this code:

Code: [Select]

if(count1 == 3){
fnSendMessageG(102,2);       
fnSendMessageG(102,2);

count2++;
}
if(count1 == 5){
fnSendMessageG(90,2);
fnSendMessageG(40,2);
count1 = 0;
}Here only the first 2 is in wireshark (01-02-2.pcapng)
I can see that the code is used but nothing comes out of the last 2 fnSendMessageG

[intern]

Hi

I have been working on solving the problem, but i just can't see why it goes wrong.

The code under here is what i am trying to get to work (try21)

Code: [Select]


                static count1 = 0;
                if(count1 == 3){
while(count2 < 8){
         fnSendMessageG(102,2);       
         fnSendMessageG(102,0);
         fnSendMessageG(90,2);
         count2++;
}
}
if(count1 == 5){

fnSendMessageG(40,2);
count1 = 0;
                        count2 = 0;
}
count1++;
}
but as you can see on the attach files not all the messages are getting send. And when i wait a bit longere the only messages getting sent is the global messages.


if i change the code to (try22)

Code: [Select]

static coun1 = 0;
                if(count1 == 3){

fnSendMessageG(102,2);       
fnSendMessageG(102,0);

}
if(count1 == 5){

fnSendMessageG(40,2);
fnSendMessageG(90,3);
count1 = 0;

}
count1++;

Do you have any idea what is wrong?
As much as i can see something goes wrong when it gets an ACK, but what i can't see..

[mark]

Hi

This is a bit of a mystery since it looks as though when you send to a non-existent address there are a number of repetitions (50ms interval) and you can then send to that address later, as you can send global messages. Once a destination has acknowledged you can't send any more to that destination.

uNetwork.c has been used for several years (in equipment installed in many locations in the world and used intensively - running on the ATMEL SAM7x) and hasn't been modified since 2008 since it has been working correctly. I don't see that it is hardware dependent in any way but there may be an issue with the Coldfire or the compiler. You could try disabling compiler optimisation just to see whether there happens to be a change in behaviour. Also note that there are some counters that can be accessed using fnGetuNetworkStats() which may show up something that aids in understanding what is happening.

If you don't make any progress please send me a zipped copy of the project (make sure that there are no .exe or .bat files as content since they will probably cause the email to be blocked) - probably it is adequate to send just the file in the application directory so that I can build it here with the same compiler and see exactly how it is configured. Assuming that I get the same behaviour I may be able to debug it more efficiently.

Regards

Mark

[intern]

Hi

I have tried what you have suggested but no change..

mail it to you, yes that can i do.. Which e-mail?
(I have sent it to info_uT@utasker.com, it was the only mail address i could find)

[mark]

That is OK - it has been received.

Regards

Mark

[mark]

Hi

I have now had the opportunity to do some tests with the M52259 and CW10.2 (I also compared with CW7.2 with no differences found).

It was not possible to use your project directly since I couldn't get it to build. I think that it would have been necessary to send the entire project, including CW10.2 settings etc. since there were various things missing.

However I did equivalent tests using the uTaskerV1.4 project doing something similar.

In your test  (try21) I think that it is clear why not all messages are being sent due to the fact that you are sending 24 message (in the x8 loop) very quickly and there are not enough buffers available (limited by #define MAX_STORED_MESSAGES      10). This means that not all can be sent since they have no retransmission buffer space. The global messages do get transmitted since they don't require a backup (never repeated) so they get out whilst the later unicast messages have to be dropped.

I concentrated on your (try22) test. The Wireshark recording is attached with 2 nodes (1 and 2) doing the same test every 10s (in both directions). At the start only one node is powered so the first test transmissions repeat until they give up. After that all looks correct. The messages sent between nodes 1 and 2 are correctly acknowledged and the ones sent to node 3 (didn't exist) are repeated a few times before they give up. It was not possible to reproduce your problem with transmissions stopping after messages had been acknowledged once. I tried various permutations to see whether there was one that could cause problems but I never had any issues after spending over half a day of expermenting.

My conclusion is that you may have a problem due to something outside of this module in your project so I would carefully check the amount of memory the project is using to see whether there could be a memory shortage causing something to get corrupted. I would also suggest repeating the tests based on the uTaskerV1.4 project without other changes to verify that you can reproduce the correct operation before moving to the final project again. Below is the code that I used based on your transmission subrouting - note that I control the periodicity of the test also at this location with the timer calling the test again each time that it fires.

There was however a modification that I made to the uNetwork.c file due to the fact that I was losing synchronisation (acknowledgement counter) when sending immediately after reset before the Ethernet link was up (and thus losing the first test messages). In the main project using this the case is never encountered so I didn't realise that this coudl happen. I don't think that it is releated in anyway to the difficulty that you have had since it has nothing to do with transmissions.

My most up to date file is also attached including this change as reference.

Code: [Select]

static void fnSendDist(void)
{
    fnSendMessageG(102,2);
    fnSendMessageG(102,0);
    fnSendMessageG(102,2);
    fnSendMessageG(102,3);

    uTaskerMonoTimer(OWN_TASK, (DELAY_LIMIT)(10 * SEC), SEND_AGAIN);
}
The timer event simply calls the test again:
            ...
else if (SEND_AGAIN == ucInputMessage[MSG_TIMER_EVENT]) {
                fnSendDist();
            }

Note that the destinations are reversed at each nodes (as you will already be aware of) so that they sent to each other.

Regards

Mark

[intern]

Have there been any changes that can affect the problem from the uTasker v1.4-0 to a newer version because i use uTasker V1.4-0?

I have sent my project to you, because i have worked with it the last days but i haven't come any nearer i solution.

[mark]

Hi

There had been no changes related to the uNetwork since 2008 (V1.4-0 dates back to August 2009).
In the meantime I have received your complete project. However I don't find a CW10.2 project in it - are you using CW7?
Please could you tell me which is the project file that you open? Is it Firmware 2.5.1\Applications\uTaskerV1.4\CodeWarrior_M5223X\uTaskerV1.4_CW7.mcp ?

Regards

Mark