diff --git a/iec1107.pm b/iec1107.pm
new file mode 100755
index 0000000..593a818
--- /dev/null
+++ b/iec1107.pm
@@ -0,0 +1,305 @@
+#!/usr/bin/perl
+# 
+# This is actually my first attempt with perl. 
+# This script borrows parts of https://wiki.volkszaehler.org/hardware/channels/meters/power/eastron_drs155m
+# which itself borrows parts of http://www.ip-symcon.de/forum/threads/21407-Stromz%C3%A4hler-mit-RS485/page2
+# The general functions have been developed in python3, see https://github.com/menschel/pyehz
+# Use and copy as you wish.
+# Menschel (C) 2020
+
+package iec1107; # we name our package iec1107 as this is the original protocol name
+
+
+use strict;
+use warnings;
+use Carp; #TODO: this is for the "ref" check
+
+use Device::SerialPort;
+
+#for time conversion
+use POSIX::strptime qw( strptime );
+use POSIX qw{strftime};
+ 
+#constants
+our $SOH = chr(0x01);
+our $STX = chr(0x02);
+our $ETX = chr(0x03);
+our $EOT = chr(0x04);
+
+our $ACK = chr(0x06);
+our $NACK = chr(0x15);
+
+our $CRLF = "\r\n";
+our $STARTCHARACTER = "/";
+our $TRANSMISSIONREQUESTCOMMAND = "?";
+our $ENDCHARACTER = "!";
+
+#function prototypes
+
+#serial transfer function
+#sub _xfer($);
+
+#read 1 message data interpretation
+#sub _interpret_r1_msg($);
+
+#scaling functions
+#sub _scale_div_by_10($);
+#sub _scale_mul_by_10($);
+#sub _scale_1_to_1($);
+#sub _scale_to_time($);
+#sub _scale_to_temp($);
+
+#calculate message checksum
+#sub _calc_bcc($);
+
+
+#message generation functions
+#sub _generate_r1_msg(%);
+#sub _generate_p1_msg(%);
+#sub _generate_b0_msg();
+#sub _generate_programming_command_message(%);
+#sub _generate_ack_optionselect_msg(%);
+#sub _generate_request_message(%);
+
+
+
+
+
+my %drs110m_values = (
+                   #'<measurement>'=>[<address>,<scalingfunction>,'<unit>'],
+                   'Voltage'       =>[ 0,\&_scale_div_by_10,  'V'],
+                   'Current'       =>[ 1,\&_scale_div_by_10,  'A'],
+                   'Frequency'     =>[ 2,\&_scale_div_by_10, 'Hz'],
+                   'Active Power'  =>[ 3, \&_scale_mul_by_10,  'W'],
+                   'Reactive Power'=>[ 4, \&_scale_mul_by_10,'VAr'],
+                   'Apparent Power'=>[ 5, \&_scale_mul_by_10, 'VA'],
+                   'Active Energy' =>[10,    \&_scale_1_to_1, 'Wh'],
+                   'Time'          =>[31,    \&_scale_to_time,   ''],
+                   'Temperature'   =>[32,    \&_scale_to_temp, '°C'],
+                  );
+
+
+sub new(\$$$){
+  #we expect a HASH consisting of a reference to a valid port, an ID and a password
+  # {"port"=>\$port,
+  #  "serialID"=>$id,
+  #  "passwd"=>$passwd,
+  #}
+  my $class = shift;
+  my $self = {@_};#creates reference to HASH
+  bless($self,$class);#changes class of $object to "drs110m"
+  $self->_init;
+  return $self;
+};
+
+sub _init {
+  my $self = shift;
+  #we expect $self->port to be setup correctly so nothing to do here
+
+  #for whatever reason _init() does not return anything in the LEARN PERL Examples
+  return;
+};
+
+sub start_communication {
+  my $self = shift;
+  my $res;
+  $res = $self->_xfer(_generate_request_message("serialnumber"=>$self->{serialID}));
+  #there is an automatic sleep from the serial timeout
+  if (!$res){
+    #a second wakeup call is not required every time but when the device was asleep.
+    $res = $self->_xfer(_generate_request_message("serialnumber"=>$self->{serialID}));
+  };
+  return $self; #utility functions should return self according to LEARN PERL examples
+};
+
+sub start_programming_mode {
+  my $self = shift;
+  my $res;
+  $res = $self->_xfer(_generate_ack_optionselect_msg("protocol"=>0,"mode"=>1));#note: mode 1 is programming mode, obviously privileges are needed for register access
+  $res = $self->_xfer(_generate_p1_msg("password"=>$self->{passwd}));
+  return $self; #utility functions should return self according to LEARN PERL examples  
+};
+
+
+sub update_values {
+  my $self = shift;
+  my $res;
+  my $valstr;
+  my $unit;
+  my ($addr,$val);
+  while ( my ($measurement, $vals) = each(%drs110m_values) ) {
+    $res = $self->_xfer(_generate_r1_msg("reg"=>$drs110m_values{$measurement}[0]));
+    ($addr,$val) = _interpret_r1_msg($res);
+    if (defined($addr)){#sanity check
+      if ($addr == $drs110m_values{$measurement}[0]){#paranoia check
+        $val = &{$drs110m_values{$measurement}[1]}($val);
+        $unit = $drs110m_values{$measurement}[2];
+        $valstr = sprintf("%15s : %s %s\n",$measurement,$val,$unit);
+        print($valstr);
+      }
+      else{
+        die("Found $addr but expected $drs110m_values{$measurement}[0]");
+      };
+    }
+    else {
+      die("No Response for $measurement");
+    };
+  }
+
+  return $self;
+};
+
+sub log_off() {
+  my $self = shift;
+  my $res;
+  $res = $self->_xfer(_generate_b0_msg());
+  return $self;
+};
+
+sub _xfer {
+  my $self = shift;
+  my ($cmd) = @_;
+  my $count;
+  my $res;
+  $self->{port}->lookclear;
+  $self->{port}->write( $cmd );
+ 
+  ($count,$res)=$self->{port}->read(32);
+
+  return $res;
+}
+
+
+#TODO: we have to include this obj class check with "ref" later
+#sub do_something() {
+#  my $self = shift;
+#   unless (ref $self){"croak Should call surname() with an object, not a class";}
+#  return $self->{surname}
+#}
+
+#TODO: we need object accessor methodes later
+# Object accessor methods
+# interesting function that writes if there is an input, apparently 
+#sub address { $_[0]->{address }=$_[1] if defined $_[1]; $_[0]->{address } }
+
+
+
+
+
+#basic functions
+
+
+sub _interpret_r1_msg($){
+  my ($str) = @_;
+  my $val;
+  my $addr;
+  if($str =~ m/\((\S+)\)/) {
+    $val = $1;
+    if($str =~ m/(\d+)\(/) {
+      $addr = $1;
+    };
+  };
+  return $addr,$val;
+};
+
+
+sub _scale_div_by_10($){
+  my ($val) = @_;
+  return $val/10;
+};
+
+sub _scale_mul_by_10($){
+  my ($val) = @_;
+  return $val*10;
+};
+
+sub _scale_1_to_1($){
+  my ($val) = @_;
+  return $val;
+};
+
+sub _scale_to_time($){
+#"19112703192714" => 2019-11-27 19:27:14 
+  my ($str) = @_;
+  #print("$str \n");
+  my $fmt = "%y%m%d0%w%H%M%S";
+  my @time = (POSIX::strptime($str,$fmt))[0..7];
+  if (wantarray){
+    return @time;
+  }
+  else{
+    return strftime("%Y-%m-%d %H:%M:%S",@time);
+  };
+};
+
+sub _scale_to_temp($){
+  my ($val) = @_;
+  my $hex = "";
+  foreach (split '',$val){
+      $hex .= sprintf("%X", ord($_)-0x30);
+    };
+  return hex($hex);
+};
+
+sub _calc_bcc($){
+  my ($val) = @_;
+  my $bcc = 0;
+  foreach (split'',substr($val,1)){
+    $bcc ^= ord($_);
+  }
+  return $bcc;
+};
+
+sub _generate_r1_msg(%){
+  my %args = @_;
+  my $reg = $args{reg};
+  my $regstr = sprintf("%08d()",$reg);
+  my $msg=_generate_programming_command_message("command"=>"R","commandtype"=>1,"data"=>$regstr);
+  return $msg;
+};
+
+
+sub _generate_p1_msg(%){
+  my %args = @_;
+  my $passwd = $args{password};
+  my $passwdstr = sprintf("(%08d)",$passwd);
+  my $msg=_generate_programming_command_message("command"=>"P","commandtype"=>1,"data"=>$passwdstr);
+  return $msg;
+};
+
+sub _generate_b0_msg(){
+  my $msg=_generate_programming_command_message("command"=>"B","commandtype"=>0,"data"=>"");
+  return $msg;
+};
+
+sub _generate_programming_command_message(%){
+  my %args = @_;
+  my $command = $args{command};
+  my $commandtype = $args{commandtype};
+  my $data = $args{data};
+  my $cmdstr = sprintf("%s%d",$command,$commandtype);
+  my $msg=$SOH.$cmdstr.$STX.$data.$ETX;
+  $msg .= chr(_calc_bcc($msg));
+  return $msg;  
+};
+
+sub _generate_ack_optionselect_msg(%){
+  my %args = @_;
+  my $protocol = $args{protocol};
+  my $mode = $args{mode};
+  my $msgstr = sprintf("%d:%d",$protocol,$mode);#the ':' is the baudrate identifier
+  my $msg=$ACK.$msgstr.$CRLF;#Todo: make the special characters nicely, note there is no bcc for this msg type
+  return $msg;
+};
+
+
+sub _generate_request_message(%){
+  my %args = @_;
+  my $serialnumber = $args{serialnumber};
+  my $snstr = sprintf("%012d",$serialnumber);
+  my $msg = $STARTCHARACTER.$TRANSMISSIONREQUESTCOMMAND.$snstr.$ENDCHARACTER.$CRLF;
+  return $msg;  
+};
+
+
+1;#for whatever reason
diff --git a/test_drs110m.pl b/test_drs110m.pl
old mode 100755
new mode 100644
index 59857d8..bb2d74a
--- a/test_drs110m.pl
+++ b/test_drs110m.pl
@@ -1,21 +1,15 @@
 #!/usr/bin/perl
 # 
-# This is actually my first attempt with perl. 
-# This script borrows parts of https://wiki.volkszaehler.org/hardware/channels/meters/power/eastron_drs155m
-# which itself borrows parts of http://www.ip-symcon.de/forum/threads/21407-Stromz%C3%A4hler-mit-RS485/page2
-# The general functions have been developed in python3, see https://github.com/menschel/pyehz
-# Use and copy as you wish.
-# Menschel (C) 2020
-
 use strict;
 use warnings;
- 
-use Device::SerialPort;
 
-#for time conversion
-use POSIX::strptime qw( strptime );
-use POSIX qw{strftime};
- 
+sub BEGIN {
+push @INC, ".";#how long did we take for this absolute simple path include ?!
+}
+
+
+use iec1107;
+
 my $port = Device::SerialPort->new("/dev/ttyUSB0") || die $!;
 $port->baudrate(9600);
 $port->databits(7);
@@ -26,252 +20,26 @@ $port->write_settings;
  
 $port->purge_all();
 $port->read_char_time(0);     # don't wait for each character
-$port->read_const_time(100); # 100 millisecond per unfulfilled "read" call
+$port->read_const_time(150); # 100 millisecond per unfulfilled "read" call - this was too short and lead into race conditions
  
-my $serialID = "001613300153";        # The serial number of the specific device 12-digits long.
+my @serialIDs = (1613300152,1613300153); 
 # It is possible to find out the device id of a single device on RS-485 9600@7E1 by sending "/?!\r\n"
 my $password = "00000000"; # Standard password 0 over 8-digits
 
 
-#constants
-my $SOH = chr(0x01);
-my $STX = chr(0x02);
-my $ETX = chr(0x03);
-my $EOT = chr(0x04);
 
-my $ACK = chr(0x06);
-my $NACK = chr(0x15);
-
-my $CRLF = "\r\n";
-my $STARTCHARACTER = "/";
-my $TRANSMISSIONREQUESTCOMMAND = "?";
-my $ENDCHARACTER = "!";
-
-#function prototypes
-
-#serial transfer function
-sub xfer($);
-
-#read 1 message data interpretation
-sub interpret_r1_msg($);
-
-#scaling functions
-sub scale_div_by_10($);
-sub scale_mul_by_10($);
-sub scale_1_to_1($);
-sub scale_to_time($);
-sub scale_to_temp($);
-
-#calculate message checksum
-sub calc_bcc($);
-
-
-#message generation functions
-sub generate_r1_msg(%);
-sub generate_p1_msg(%);
-sub generate_b0_msg();
-sub generate_programming_command_message(%);
-sub generate_ack_optionselect_msg(%);
-sub generate_request_message(%);
-
-
-
-
-
-
-
-
-#main() starts here 
-
-my %drs110m_values = (
-                   #'<measurement>'=>[<address>,<scalingfunction>,'<unit>'],
-                   'Voltage'       =>[ 0,\&scale_div_by_10,  'V'],
-                   'Current'       =>[ 1,\&scale_div_by_10,  'A'],
-                   'Frequency'     =>[ 2,\&scale_div_by_10, 'Hz'],
-                   'Active Power'  =>[ 3, \&scale_mul_by_10,  'W'],
-                   'Reactive Power'=>[ 4, \&scale_mul_by_10,'VAr'],
-                   'Apparent Power'=>[ 5, \&scale_mul_by_10, 'VA'],
-                   'Active Energy' =>[10,    \&scale_1_to_1, 'Wh'],
-                   'Time'          =>[31,    \&scale_to_time,   ''],
-                   'Temperature'   =>[32,    \&scale_to_temp, '°C'],
-                  );
-#generate messages first and only once for a run
-my %msgs = ();
-while ( my ($measurement, $vals) = each(%drs110m_values) ) {
-  $msgs{$measurement} = generate_r1_msg("reg"=>$drs110m_values{$measurement}[0]);
-};
-
-
-
-#communication part starts here
-my $res;
-
-$res = xfer(generate_request_message("serialnumber"=>$serialID));
-#there is an automatic sleep from the serial timeout
-if (!$res){
-  #a second wakeup call is not required every time but when the device was asleep.
-  $res = xfer(generate_request_message("serialnumber"=>$serialID));
-};
- 
- 
-$res = xfer(generate_ack_optionselect_msg("protocol"=>0,"mode"=>1));#note: mode 1 is programming mode, obviously privileges are needed for register access
-$res = xfer(generate_p1_msg("password"=>$password));
-
- 
-
-my $valstr;
-my $unit;
-my ($addr,$val);
-while ( my ($measurement, $vals) = each(%drs110m_values) ) {
-  $res = xfer( $msgs{$measurement} );
-  ($addr,$val) = interpret_r1_msg($res);
-  if (defined($addr)){#sanity check
-    if ($addr == $drs110m_values{$measurement}[0]){#paranoia check
-      $val = &{$drs110m_values{$measurement}[1]}($val);
-      $unit = $drs110m_values{$measurement}[2];
-      $valstr = sprintf("%15s : %s %s\n",$measurement,$val,$unit);
-      print($valstr);
-    }
-    else{
-      die("Found $addr but expected $drs110m_values{$measurement}[0]");
-    }
-  }
-  else {
-    die("No Response for $measurement");
-  }
+for my $serialID (@serialIDs) {
+  my $drs110m =   iec1107->new("port"=>$port,"serialID"=>$serialID,"passwd"=>$password);
 
+  #print("start communication to $serialID\n");
+  print("Meter: $serialID\n");
+  $drs110m->start_communication();
+  #print("start programming mode\n");
+  $drs110m->start_programming_mode();
+  #print("update values\n");
+  $drs110m->update_values();
+  #print("log off from $serialID\n");
+  $drs110m->log_off();
 }
 
-#log off
-$res = xfer(generate_b0_msg());
-
-
-
-#functions
-sub xfer($){
-  my ($cmd) = @_;
-  my $count;
-  my $res;
- 
-  $port->lookclear;
-  $port->write( $cmd );
- 
-  ($count,$res)=$port->read(32);
-
-  return $res;
-}
-
-sub interpret_r1_msg($){
-  my ($str) = @_;
-  my $val;
-  my $addr;
-  if($str =~ m/\((\S+)\)/) {
-    $val = $1;
-    if($str =~ m/(\d+)\(/) {
-      $addr = $1;
-    };
-  };
-  return $addr,$val;
-};
-
-
-sub scale_div_by_10($){
-  my ($val) = @_;
-  return $val/10;
-};
-
-sub scale_mul_by_10($){
-  my ($val) = @_;
-  return $val*10;
-};
-
-sub scale_1_to_1($){
-  my ($val) = @_;
-  return $val;
-};
-
-sub scale_to_time($){
-#"19112703192714" => 2019-11-27 19:27:14 
-  my ($str) = @_;
-  #print("$str \n");
-  my $fmt = "%y%m%d0%w%H%M%S";
-  my @time = (POSIX::strptime($str,$fmt))[0..7];
-  if (wantarray){
-    return @time;
-  }
-  else{
-    return strftime("%Y-%m-%d %H:%M:%S",@time);
-  };
-};
-
-sub scale_to_temp($){
-  my ($val) = @_;
-  my $hex = "";
-  foreach (split '',$val){
-      $hex .= sprintf("%X", ord($_)-0x30);
-    };
-  return hex($hex);
-};
-
-sub calc_bcc($){
-  my ($val) = @_;
-  my $bcc = 0;
-  foreach (split'',substr($val,1)){
-    $bcc ^= ord($_);
-  }
-  return $bcc;
-};
-
-sub generate_r1_msg(%){
-  my %args = @_;
-  my $reg = $args{reg};
-  my $regstr = sprintf("%08d()",$reg);
-  my $msg=generate_programming_command_message("command"=>"R","commandtype"=>1,"data"=>$regstr);
-  return $msg;
-};
-
-
-sub generate_p1_msg(%){
-  my %args = @_;
-  my $passwd = $args{password};
-  my $passwdstr = sprintf("(%08d)",$passwd);
-  my $msg=generate_programming_command_message("command"=>"P","commandtype"=>1,"data"=>$passwdstr);
-  return $msg;
-};
-
-sub generate_b0_msg(){
-  my $msg=generate_programming_command_message("command"=>"B","commandtype"=>0,"data"=>"");
-  return $msg;
-};
-
-sub generate_programming_command_message(%){
-  my %args = @_;
-  my $command = $args{command};
-  my $commandtype = $args{commandtype};
-  my $data = $args{data};
-  my $cmdstr = sprintf("%s%d",$command,$commandtype);
-  my $msg=$SOH.$cmdstr.$STX.$data.$ETX;
-  $msg .= chr(calc_bcc($msg));
-  return $msg;  
-};
-
-sub generate_ack_optionselect_msg(%){
-  my %args = @_;
-  my $protocol = $args{protocol};
-  my $mode = $args{mode};
-  my $msgstr = sprintf("%d:%d",$protocol,$mode);#the ':' is the baudrate identifier
-  my $msg=$ACK.$msgstr.$CRLF;#Todo: make the special characters nicely, note there is no bcc for this msg type
-  return $msg;
-};
-
-
-sub generate_request_message(%){
-  my %args = @_;
-  my $serialnumber = $args{serialnumber};
-  my $snstr = sprintf("%012d",$serialnumber);
-  my $msg = $STARTCHARACTER.$TRANSMISSIONREQUESTCOMMAND.$snstr.$ENDCHARACTER.$CRLF;
-  return $msg;  
-};
-
-