Update media_player.onkyo.markdown

source/_components/media_player.onkyo.markdown

@@ -22,3 +22,71 @@ media_player:
   platform: onkyo
 ```
 
+A few notes:
+- Source selection has no front-end UI, but can be controlled by way of service calls. Select the source string from the following list:
+
+```
+  video1
+  video2
+  video3
+  video4
+  video5
+  video6
+  video7
+  dvd
+  bd-dvd
+  tape1
+  tv-tape
+  tape2
+  phono
+  cd
+  tv-cd
+  fm
+  am
+  tuner
+  dlna
+  internet-radio
+  usb
+  network
+  universal-port
+  multi-ch
+  xm
+  sirius
+  ```
+- Sample automation and input select
+```
+automation:
+  alias: Receiver Source
+  trigger:
+    platform: state
+    entity_id: input_select.receiver_source
+  action:
+    service: media_player.select_source
+    data_template:
+      entity_id: media_player.txnr535_000000000000
+      source: >
+        {% if is_state('input_select.receiver_source', 'HTPC') %}
+          pc
+        {% elif is_state('input_select.receiver_source', 'Chromecast') %}
+          aux1
+        {% elif is_state('input_select.receiver_source', 'Wii U') %}
+          game
+        {% elif is_state('input_select.receiver_source', 'Bluray') %}
+          bd
+        {% elif is_state('input_select.receiver_source', 'Raspberry Pi') %}
+          tv
+        {% endif %}
+        
+input_select:
+  receiver_source:
+  name: Source
+  options:
+    - HTPC
+    - Chromecast
+    - Wii U
+    - Bluray
+    - Raspberry Pi
+  initial: None
+
+```
+