I'm wanting a serial port monitor that displays the received data as hexadecimal and when it receives "01" it moves to a new line and starts the line with the time or elapsed time (format of time is not critical, I just want at least 1/10 second resolution for the time between messages). Seemed like a fairly simple thing to get started with but I'm not getting very far. Before I added the ord() it would just hang with no errors or output. After adding the ord() it outputs a continuous string of repeating "30". This is on XP with ActiveState perl.

 
#!/usr/bin/perl

use strict;
use warnings;

use Win32::SerialPort;
use Time::HiRes;


my $PORT      = "COM1";          # port to watch
my $now;
my $hex;
my $inbyte;

print "prog start \n";


my $starttime;
$starttime = Time::HiRes::time();

$now = Time::HiRes::time() - $starttime;
print "Before serial port iniialization time is: $now \n";


my $port = Win32::SerialPort->new($PORT) || die "Can't Open $PORT: $!"
+;
$port->databits(8);
$port->baudrate(9600);
$port->parity("none");
$port->stopbits(1);

while(1) {
  $inbyte=ord($port->read(1));
  $hex = unpack('H2', "$inbyte");

  if ($inbyte == 1){   # assume this is start of new packet
    $now = Time::HiRes::time() - $starttime;
    print "\n $now $hex";
    }
  else  {
    print " ", $hex;
    }
}
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