The plot thickens... I reset the comm port back to com3 just to be safe.

(I set it to Com 1 because the Serial Port module install seemed to demand a Com 1 test!) Although moving the port to com1 let me get farther in the module install, it still failed until I did a force. That installed it, but maybe that is part of the problem?

I now get this:

write failed: The handle is invalid at C:\Users\Frank\Desktop\micro-2.pl line 32

#! C:\perl\bin\perl.exe

use strict;
use warnings;

use Win32::SerialPort ;

my $count_out = 0;

my $PortObj = new Win32::SerialPort("COM3") 
       || die "Can't open port\n"; 
   
 $PortObj->error_msg(1);
 $PortObj->user_msg(1);

  $PortObj->baudrate(9600);
  $PortObj->parity("none");
  $PortObj->databits(8);
  $PortObj->stopbits(1);
  $PortObj->handshake("none");

$PortObj->write_settings || undef $PortObj;
   my $stt = pack 'H16', 'FF010003005F630A' ;

$count_out = $PortObj->write($stt) or die "write failed: $^E";
warn "write failed\n" unless $count_out;

warn "write incomplete\n" if $count_out != length($stt);

$PortObj->close || warn "Close Failed!\n";
undef $PortObj;
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