diff --git a/a.rb b/a.rb
new file mode 100755
index 0000000..55fc6aa
--- /dev/null
+++ b/a.rb
@@ -0,0 +1,73 @@
+#!/usr/bin/env ruby
+#encoding: utf-8
+
+$: << 'lib'
+
+require 'biju'
+require 'pp'
+
+str = 'www.ruby-lang.org and bonjour www.rubygarden.org coucou'
+#re = /
+#      (               # capture the hostname in $1
+#        (?:           # these parens for grouping only
+#          (?! [-_] )  # lookahead for neither underscore nor dash
+#          [\w-] +     # hostname component
+#          \.          # and the domain dot
+#        ) +           # now repeat that whole thing a bunch of times
+#        [A-Za-z]      # next must be a letter
+#        [\w-] +       # now trailing domain part
+#      )               # end of $1 capture
+#     /x               # /x for nice formatting
+re = /
+      (               # capture the hostname in $1
+        (?:           # these parens for grouping only
+          (?! [-_] )  # lookahead for neither underscore nor dash
+          [\w-] +     # hostname component
+          \.          # and the domain dot
+        ) +           # now repeat that whole thing a bunch of times
+        [A-Za-z]      # next must be a letter
+        [\w-] +       # now trailing domain part
+      )               # end of $1 capture
+     /x               # /x for nice formatting
+
+str.gsub! re do      # pass a block to execute replacement
+  pp $1
+end
+
+#exit
+
+puts "here"
+hayes = Biju::HayesSms.new
+pp hayes.attention
+pp hayes.answer = 'OK'
+pp hayes.ok?
+pp hayes.init_modem
+pp hayes.answer = 'OK'
+pp hayes.ok?
+pp hayes.text_mode
+pp (hayes.answer = 'OK')
+pp hayes.ok?
+pp hayes.prefered_storage?
+pp hayes.answer = '+CPMS: ("ME","MT","SM","SR"),("ME","MT","SM","SR"),("ME","MT","SM","SR")'
+# ((),(),())
+# (),(),()
+# 1,2
+
+pp hayes.ok?
+
+exit
+
+@modem = Biju::Modem.new(:port => "/dev/ttyUSB0", :pin => '2382')
+
+# method to list all messages
+@modem.messages.each do |sms|
+  puts sms
+end
+
+# method to send sms
+sms = Biju::Sms.new(:phone_number => "0668486469", :message => 'hello world3')
+puts @modem.send(sms)
+
+@modem.close
+
+
diff --git a/biju.gemspec b/biju.gemspec
index 98fe990..a4aa2a4 100644
--- a/biju.gemspec
+++ b/biju.gemspec
@@ -17,5 +17,5 @@ Gem::Specification.new do |gem|
 
   gem.add_development_dependency "minitest",    "3.0.0"
 
-  gem.add_dependency "serialport",              "1.0.4"
+  gem.add_dependency "serialport",              ">=1.0.4"
 end
diff --git a/lib/biju.rb b/lib/biju.rb
index a7a08b6..656b999 100644
--- a/lib/biju.rb
+++ b/lib/biju.rb
@@ -1,3 +1,4 @@
 require 'biju/version'
 require "biju/modem"
 require "biju/sms"
+require "biju/hayes"
diff --git a/lib/biju/hayes.rb b/lib/biju/hayes.rb
new file mode 100644
index 0000000..6f68bb1
--- /dev/null
+++ b/lib/biju/hayes.rb
@@ -0,0 +1,72 @@
+module Biju
+  class Hayes
+    attr_accessor :command, :attributes, :ok
+    attr_reader :answer
+
+    #def method_missing(m, *args, &block)
+    #end
+
+    def attention
+      basic_command { |response| response =~ /OK/ }
+      #basic_command { |response| true }
+    end
+
+    def init_modem
+      basic_command('Z') { |response| response =~ /OK/ }
+    end
+
+    def text_mode(enabled = true)
+      extended_command('CMGF', enabled) { |response| response =~ /OK/ }
+    end
+
+    def prefered_storage?
+      extended_command('CPMS') { |response| response =~ /OK/ }
+    end
+
+    def answer=(ret)
+      @answer = ret
+      ok?
+    end
+
+    def ok?
+      ok.nil? ? true : !ok.call(answer).nil?
+    end
+
+    private
+
+    def basic_command(cmd = nil, options = {}, *args, &block)
+      option_prefix = options[:prefix] || nil
+      cmd_root = ['AT', cmd].compact.join(option_prefix)
+      cmd_args = args.compact.map { |arg| to_hayes_string(arg) } unless args.empty?
+      self.command = [cmd_root, cmd_args].compact.join('=')
+      self.ok = block if block_given?
+      command
+    end
+
+    def extended_command(cmd = nil, *args, &block)
+      basic_command(cmd, {:prefix => '+'}, *args, &block)
+    end
+
+    def hayes_to_obj(str)
+    end
+
+    def to_hayes_string(arg)
+      case arg
+      when String
+        "\"#{arg}\""
+      when Array
+        arg.join(',')
+      when TrueClass, FalseClass
+        !!arg ? 1 : 0
+      else
+        "?"
+      end
+    end
+  end
+
+  class HayesSms < Hayes
+    def unlock_pin(pin)
+      send_command("AT+CPIN=#{to_hayes_string(pin)}") { |response| response =~ /OK/ }
+    end
+  end
+end
diff --git a/lib/biju/modem.rb b/lib/biju/modem.rb
index b9bf222..b55f2b8 100644
--- a/lib/biju/modem.rb
+++ b/lib/biju/modem.rb
@@ -3,6 +3,7 @@ require_relative 'sms'
 
 module Biju
   class Modem
+    attr_reader :connection
 
     # @param [Hash] Options to serial connection.
     # @option options [String] :port The modem port to connect
@@ -11,23 +12,30 @@ module Biju
     #
     def initialize(options={}, &block)
       raise Exception.new("Port is required") unless options[:port]
-      pin = options.delete(:pin)
-      @connection = connection(options)
+      pin = options[:pin] || '0000'
+      @connection = connect(options)
       cmd("AT")
       # initialize modem
       cmd("ATZ")
       # unlock pin code
       cmd("AT+CPIN=\"#{pin}\"") if pin
+
+      cmd("AT+CPMS=?")
+
       # set SMS text mode
       cmd("AT+CMGF=1")
       # set extended error reports
       cmd('AT+CMEE=1')
       #instance_eval &block if block_given?
+      if block_given?
+        yield connection
+        close
+      end
     end
 
     # Close the serial connection.
     def close
-      @connection.close
+      connection.close
     end
 
     # Return an Array of Sms if there is messages nad return nil if not.
@@ -60,7 +68,7 @@ module Biju
     end
 
     private
-    def connection(options)
+    def connect(options)
       port = options.delete(:port)
       SerialPort.new(port, default_options.merge!(options))
     end
@@ -70,17 +78,19 @@ module Biju
     end
 
     def cmd(cmd)
-      @connection.write(cmd + "\r")
+puts "SENDING : #{cmd}"
+      connection.write(cmd + "\r")
       wait_str = wait
       #p "#{cmd} --> #{wait_str}"
     end
 
     def wait
       buffer = ''
-      while IO.select([@connection], [], [], 0.25)
-        chr = @connection.getc.chr;
+      while IO.select([connection], [], [], 0.25)
+        chr = connection.getc.chr;
         buffer += chr
       end
+puts "RECEIVING : #{buffer}"
       buffer
     end
   end