Hi all,

I'm having a bit of a problem with Telnet and Modbus.

I'm trying to send a packet over to a Modbus slave but Telnet.pm is attaching a CRLF (0d 0a) to the end of my packet and it's confusing my Modbus slave. I am unsure how to prevent the module from sending the last packet! My send code is attached below. I've tried changing binmode but all it does is change whether CR or LF is being sent. Help please. Thanks!

Regards, Paul.

Example sent packet: 01 06 07 D0 00 00 89 47 0A

What I need: 01 06 07 D0 00 00 89 47

                $data = join('',@buffor);                           #M
+odbus frame to scalar
                print "ASCII characters sent: $data\n";
                if ($Telnet) {
                        #print "Sending over telnet\n";
                        $pass=$ob->print($data)
                        or warn "Modbus client : problem with send: $!
+\n";

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In reply to Telnet.pm Sending CRLF by PaulNg

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