Class: Simatic::Sessions::OpenSession

Inherits:
ExchangeSession show all
Defined in:
lib/simatic/sessions/open_session.rb

Overview

Open Communication Request->Response session class going second

Instance Method Summary collapse

Methods inherited from Session

#packet_number

Constructor Details

#initialize(max_pdu_length = nil) ⇒ OpenSession

Returns a new instance of OpenSession.



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# File 'lib/simatic/sessions/open_session.rb', line 7

def initialize max_pdu_length = nil
  @@max_pdu_length = max_pdu_length if max_pdu_length
end

Instance Method Details

#make_request ⇒ Object 



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# File 'lib/simatic/sessions/open_session.rb', line 11

def make_request
  param = [FuncOpenS7Connection, 0x00, 0x00, 0x01, 0x00, 0x01, @@max_pdu_length].pack('C6n')
  super param
end

#parse_response(raw_data) ⇒ Object 



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# File 'lib/simatic/sessions/open_session.rb', line 16

def parse_response raw_data
  super

  unless FuncOpenS7Connection == @function
    raise "unknown function 0x#{@function.to_s(16)} in #{self.class} response"
  end

  @@max_pdu_length = @params[6,2].unpack('n').first
end