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examples/tk_disp_reg.pl  view on Meta::CPAN

$m->host("127.0.0.1");
$m->unit_id(1);

# open TCP socket
if (! $m->open()) {
  print "unable to open TCP socket.\n";
  exit(1);
}

# sub to update modbus_val (call by a tk timer)
sub update_modbus() {
  my $words = $m->read_holding_registers(0, 1);
  $modbus_val = $words->[0]."\n";
}

# init Tk
my $mw = tkinit();

# build modbus label area
my $modbus_label = $mw->Label(
  -textvariable => \$modbus_val,