Adding protocol documentation

README.md

@@ -76,7 +76,7 @@ device.destroy();
 
 ## Tokens
 
-A few Miio devices send back their token during a handshake and can be used
+A few miIO devices send back their token during a handshake and can be used
 without figuring out the token. Most devices hide their token, such as
 Yeelights and the Mi Robot Vacuum.
 
@@ -192,19 +192,19 @@ Get information and update the wireless settings of devices via the management
 API.
 
 Discover the token of a device:
-```
+```javascript
 device.discover()
 	.then(info => console.log(info.token));
 ```
 
 Get internal information about the device:
-```
+```javascript
 device.management.info()
 	.then(console.log);
 ```
 
 Update the wireless settings:
-```
+```javascript
 device.management.updateWireless({
 	ssid: 'SSID of network',
 	passwd: 'Password of network'
@@ -216,4 +216,6 @@ creating its own network if the settings are invalid.
 
 ## Protocol documentation
 
-This library is based on the documentation provided by OpenMiHome. See https://github.com/OpenMiHome/mihome-binary-protocol for details.
+This library is based on the documentation provided by OpenMiHome. See https://github.com/OpenMiHome/mihome-binary-protocol for details. For details
+about how to figure out the commands for new devices look at the
+[documentation for protocol and commands](docs/protocol.md).

docs/protocol.md

@@ -0,0 +1,64 @@
+# Protocol and commands
+
+The base protocol is based on documentation provided by OpenMiHome. See https://github.com/OpenMiHome/mihome-binary-protocol for details. This
+protocol defines how packets are sent to and from the devices are structured,
+but does not describe the commands that can be issued to the devices.
+
+Currently the best way to figure out what commands a device supports is to
+run a packet capture with Wireshark between the Mi Home app and your device.
+The `miio` command line app can the be used together with JSON export from
+Wireshark to extract messages sent back and forth.
+
+First make sure you have installed the `miio` app:
+
+`npm install -g miio`
+
+## Creating a capture
+
+### Figure out your device token before starting
+
+If you do not have the token of your device yet, run `miio --discover` to list
+devices on your network and their auto-extracted tokens. If the token is not
+found, follow the [instructions to find device tokens](tokens.md). This needs
+to be done before you start your capture or the capture will be useless as
+resetting the device will generate a new token.
+
+### Running Wireshark and Mi Home
+
+If you have knowledge about Wireshark you can run a capture however you like,
+but if you do not the easiest way is to use the method described in the
+readme of [Homey app for Xiaomi Mi Robot Vaccum Cleaner](https://github.com/jghaanstra/com.robot.xiaomi-mi) to capture the
+traffic.
+
+## Analyzing the capture
+
+### Exporting the packets as JSON
+
+The first step is to export the capture from Wireshark as a JSON file. You
+should be able to extract a file with all your traffic, but you might want to
+apply a filter in Wireshark to limit the size of the file.
+
+A good starting filter is: `udp.dstport == 54321 or udp.srcport == 54321`
+
+### Running the `miio` app
+
+To extract messages sent back and forth and dump to your terminal:
+
+`miio --token tokenAsHex --json-dump path/to/file.json`
+
+### Figuring out the output
+
+The output will be filled with output such as this:
+
+```
+-> 192.168.100.7 data={"id":10026,"method":"get_status","params":[]}
+<- 192.168.100.8 data={ "result": [ { "msg_ver": 4, "msg_seq": 238, "state": 6, "battery": 100, "clean_time": 21, "clean_area": 240000, "error_code": 0, "map_present": 1, "in_cleaning": 0, "fan_power": 60, "dnd_enabled": 1 } ], "id": 10026 }
+```
+
+Lines starting with `->` are messages sent to a device and `<-` are messages
+from a device. If the data is `N/A` it was either a handshake or the message
+could not be decoded due to an invalid token.
+
+The `method` and `params` property in outgoing messages can be plugged into
+`device.call(method, params)` to perform the same call. Go through and see what
+the Mi Home app calls and how the replies look.

package.json

@@ -2,7 +2,7 @@
   "name": "miio",
   "version": "0.5.0",
   "license": "MIT",
-  "description": "Control Mi Home devices implementing the Miio protocol, such as Mi Robot Vacuums, Mi Air Purifiers and more",
+  "description": "Control Mi Home devices implementing the miIO protocol, such as Mi Robot Vacuums, Mi Air Purifiers and more",
   "repository": "aholstenson/miio",
   "main": "lib/index.js",
   "keywords": [