Karabiner private.xml for non-Apple keyboard to toggle Target Display Mode

private.xml

<?xml version="1.0"?>
<root>
  <devicevendordef>
    <vendorname>LOGITECH</vendorname>
    <vendorid>0x046d</vendorid>
  </devicevendordef>
  
  <deviceproductdef>
    <productname>LOGITECH_K811</productname>
    <productid>0xb317</productid>
  </deviceproductdef>
  
  <item>
    <name>Cmd + F2 to toggle TDM (Logitech_K811)</name>
    <appendix>Cmd + F2 for Target Display Mode</appendix>
    <identifier>private.logitch_K811_toggle_TMD</identifier>
    <!-- Comment the line below to remove restriction to mapping Logitech K811 only -->
    <device_only>DeviceVendor::LOGITECH, DeviceProduct::LOGITECH_K811</device_only>
    <!--Target Display Mode-->
    <autogen>__KeyToKey__ KeyCode::F2, VK_COMMAND, ConsumerKeyCode::BRIGHTNESS_UP, ModifierFlag::COMMAND_L</autogen>
<!--
    <autogen>__KeyToKey__ KeyCode::F6, VK_COMMAND, ConsumerKeyCode::BRIGHTNESS_DOWN, ModifierFlag::FN</autogen>
    <autogen>__KeyToKey__ KeyCode::F7, VK_COMMAND, ConsumerKeyCode::BRIGHTNESS_UP, ModifierFlag::FN</autogen>
-->
  </item>

  <devicevendordef>
    <vendorname>MADCATZ</vendorname>
    <vendorid>0x0738</vendorid>
  </devicevendordef>
  
  <deviceproductdef>
    <productname>MADCATZ_STRIKEM</productname>
    <productid>0x1114</productid>
  </deviceproductdef>
  
  <item>
    <name>Cmd + F5 or F6 to adjust Adjust Brightness (Madcatz)</name>
    <appendix>Cmd + F2 for Target Display Mode - Command F5 or F6 brightness up/down.</appendix>
    <identifier>private.madcatz_strikem_toggle_TMD</identifier>
    <!-- Comment the line below to remove restriction to mapping Madcatz Strikem only -->
    <device_only>DeviceVendor::MADCATZ, DeviceProduct::MADCATZ_STRIKEM</device_only>   
    <!--Target Display Mode-->
    <autogen>__KeyToKey__ KeyCode::F2, VK_COMMAND, ConsumerKeyCode::BRIGHTNESS_UP, ModifierFlag::COMMAND_L</autogen>
    <!-- Fn+F1F6,F7 to Brightness Adjust -->
    <autogen>__KeyToKey__ KeyCode::F6, VK_COMMAND, ConsumerKeyCode::BRIGHTNESS_DOWN, ModifierFlag::FN</autogen>
    <autogen>__KeyToKey__ KeyCode::F7, VK_COMMAND, ConsumerKeyCode::BRIGHTNESS_UP, ModifierFlag::FN</autogen>
  </item>
</root>

For use with Karabiner App on Mac OS X. In Karabiner app, settings, open EventViewer to get Device ID & Vendor ID for your keyboard, and then use <device_only> in private.xml to limits keyboard remapping to certain keybaords. I find this useful for using _'Target Display Mode'_ on a Mac (with a non Apple Keyboard, like the great _Logitech K811_).