Sending UDP Packets from Perl Script to SImulink

Hello Everyone ,

I have bunch of numbers which I get from a hardware which needs to be sent to Simulink via UDP-Ethernet connection. I tried to use UDP Receive block in Simulink and exported the data to workspace. But I am not able to get any data .. What i get is all zeros.

Here is the sample Perl Script

   #!/usr/bin/perl
  #udpclient.pl

use IO::Socket;
use warnings;
use Time::HiRes qw (sleep);

my ($socket,$data);
#my $in_file_name = $ARGV[0];
$in_file_name='C:\Users\PQRST\Documents\Example.csv';

open(INFILE,"<",$in_file_name) or die "Not able to open test file $!";

$socket = IO::Socket::INET->new (PeerAddr   => 'localhost',
                                 PeerPort  => 5005,
                                 Type      => SOCK_DGRAM,
                                 Proto      => 'udp') or die "ERROR in
+ Socket Creation : $!\n";

while (<INFILE>)
{
    chomp;
    if($. != 1) #skip first line
    {
        $data=$_;  # Data would be in String format

          $socket->send("$data");
          sleep(0.25);
      } 

}

$socket->close();

Instead of directly running the script on hardware , I am just sending the data to myself ("localhost") and I am keeping '0.0.0.0' at port 5005 to receive data from all. Can anyone give me insight on this .. Any help would be appreciated...

[Walter Roberson]

Did you experiment with sending a constant string and seeing what comes out?

[A P S]

Hello Roberson, Thanks for your reply. Yes, I did try the simple String like "Hello" . I received ASCII Value of HELLO>.. Like repeated values of 72 101 108 108 111 ... but I am not sure why I can't just send numbers.. Got to do with some Datatypei issues.. The Script and model used is same as below.. Instead I just Sent Repeated "Hello"

Answer 1

[Pawel Ladosz]

Hi A P S,

Usually when we had this type of problem it was either of two things:

1. Your data type/length is not defined correctly on UDP receive end (less likely as you have managed to have some success before)

2. Your data is not being received/send on right ip adress/port. Instead of defining your address as localhost in your pearl script I recommend you define it as actual IP address (IP address of machine you are on). Same goes for UDP receive, just define IP of receiver as the machine you are on.

Let me know if this worked for you

[A P S]

Hello Pawel, Thanks for your tips. I think I am not using correct datatype/length on UDP Receive side. Here is the snapshot of model.

And Here are the Settings..

And Here are the settings block for Workspace..

*********************************************************** As you have mentioned , I have kept the Machine IP Address .Here is the Perl Script I used which i believe is correct..

   #!/usr/bin/perl
  #udpclient.pl

use IO::Socket;
use warnings;
use Time::HiRes qw (sleep);

my ($socket,$data);

$socket = IO::Socket::INET->new (PeerAddr   => '10.11.2XX.XX',
                                 PeerPort  => 12345,
                                 Type      => SOCK_DGRAM,
                                 Proto      => 'udp') or die "ERROR in
+ Socket Creation : $!\n";

#@tempData = (20,30,40);
#$socket->send(pack ("(A*)*", @tempData));
for (my $i=0; $i <= 999; $i++) {
   print "$i\n";
   $socket->send(112233);
}
$socket->close();

And What I received is is 1000x1 Uint8 array of zeros and 49's 50's ...

I am pretty sure that I am making some mistake on Data Type Selection and Length Stuff.. Do you have nay suggetions. ?

[Walter Roberson]

In

$socket->send(112233)

what data type is 112233 ? 64 bit signed integer? Double precision?

[A P S]

Double Precision Mr.Roberson

[Pawel Ladosz]

Change your "data Type" to Double and leave length as 1 in UDP receive2 block. Also for testing I recommend you attach a Display block and see what is going on much quicker