lib/prologix_gpib/lan.rb in prologix_gpib-0.5.0 vs lib/prologix_gpib/lan.rb in prologix_gpib-0.5.2

@@ -1,14 +1,16 @@
+require 'timeout'
+
 module PrologixGpib::Lan
   class Error < StandardError
   end
 
   DEVICE_PORT = 1234
-  EOL = "\r\n"
+  EOL = "\r\n".freeze
 
   def initialize(ip, mode: :controller, address: 9)
-    @socket = TCPSocket.new ip, DEVICE_PORT
+    open_socket(ip)
 
     # open_serial_port(paths)
     # flush
     # self.mode = mode
     # self.address = address
@@ -16,10 +18,53 @@
     # self.eos = 0
 
     yield self if block_given?
   end
 
-  def version
-    @socket.send "++ver#{EOL}", 0
+  def write(command)
+    return unless connected?
+
+    @socket.send "#{command}#{EOL}", 0
+    sleep 0.1
+  end
+
+  def read
+    return unless connected?
+
     @socket.gets.chomp
+  end
+
+  private
+
+  def open_socket(ip)
+    @socket = TCPSocket.new ip, DEVICE_PORT
+    write('++ver')
+    return if getline.include? 'Prologix'
+
+    raise Error, 'No Prologix LAN controllers found.'
+  end
+
+  def connected?
+    raise Error, 'ConnectionError: No open Prologix device connections.' if @socket.nil?
+
+    true
+  end
+
+  def readline
+    return unless connected?
+
+    t = Timeout.timeout(1, Timeout::Error, "No response from device at #{@socket.peeraddr[3]}") { getline }
+  end
+
+  # This method will block until the EOL terminator is received
+  # The lower level gets method is pure ruby, so can be safely used with Timeout.
+  def getline
+    return unless connected?
+
+    @socket.gets(EOL).chomp
+  end
+
+  def device_query(command)
+    write(command)
+    readline
   end
 end