title: Unable to write to BLE112 Characteristic with Pygatt and BLE112
body: <p>I have been trying for a while to write to a custom gatt characteristic using pygatt and a Bluegiga BLE112D.The device I'm trying to write to is also a BLE112 (not the dongle). I've been using the following python script:</p>
  
  <pre><code>import pygatt
  
  adapter = pygatt.BGAPIBackend()
  
  adapter = pygatt.BGAPIBackend()
  adapter.start()
  adapter.scan(timeout=1)
  
  device = adapter.connect('88:6b:0f:7e:4e:66',address_type=pygatt.BLEAddressType.public)
  characteristic = "8fbfa190-1af2-427c-a22b-3da61b6b7162"
  device.char_write(characteristic, bytearray([0x00, 0xFF]))
  
  #check the characteristic
  value = device.char_read(characteristic)
  
  print(value)
  adapter.stop()
  </code></pre>
  
  <p>The characteristic I am trying to write to is configured as follows:</p>
  
  <pre><code>&lt;service uuid="8fbfa190-1af2-427c-a22b-3da71b6b7166" advertise="true"&gt;
    &lt;description&gt;Table&lt;/description&gt;
    &lt;include id="manufacturer" /&gt;
    &lt;characteristic uuid="8fbfa190-1af2-427c-a22b-3da61b6b7162" id="xgatt_table"&gt;
        &lt;properties read="true" write="true" /&gt;
        &lt;value length="2" /&gt;
    &lt;/characteristic&gt;
  &lt;/service&gt;
  </code></pre>
  
  <p>-The script successfully connects with the adapter and the device. 
  -I can read the characteristic just fine and no errors are produced when I write to it, but when I read the characteristic again, the value has not changed. 
  -I've enabled logging and looked through the output, but everything there shows successful processes. 
  -I am able to write to the characteristic using a third party BLE app as well as the blegui app</p>
  
  <p>I'm pretty sure the problem resides with the pygatt script, but am at a loss as to what could be the issue. </p>
  
  <p>To summarize what I'm using: Pygatt with python 3 to connect to a BLE112A through a BLE112D on windows 10.</p>