-The expected format of a single valued message is:
-
- {"name": "steering_wheel_angle", "value": 45}
-
-## Evented
-
-The expected format of an event message is:
-
- {"name": "button_event", "value": "up", "event": "pressed"}
-
-This format is good for something like a button event, where there are two
-discrete pieces of information in the measurement.
-
-## Raw CAN Message format
-
-An OpenXC vehicle interface may also output raw CAN messages. Each CAN message
-is sent as a JSON object, separated by newlines. The format of each object is:
-
- {"bus": 1, "id": 1234, "value": "0x12345678"}
-
-**bus** - the numerical identifier of the CAN bus where this message originated,
- most likely 1 or 2 (for a vehicle interface with 2 CAN controllers).
-
-**id** - the CAN message ID
-
-**data** - up to 8 bytes of data from the CAN message's payload, represented as
- a hexidecimal number in a string. Many JSON parser cannot handle 64-bit
- integers, which is why we are not using a numerical data type.
-
-## Diagnostic Messages
-
-### Requests
-
-A request to add or update a diagnostic request is sent to a vehicle interface
-with this command format:
-
- { "command": "diagnostic_request",
- "request": {
- "bus": 1,
- "id": 1234,
- "mode": 1,
- "pid": 5,
- "payload": "0x1234",
- "parse_payload": true,
- "multiple_response": false,
- "factor": 1.0,
- "offset": 0,
- "frequency": 1,
- "name": "my_pid"
- }
- }
- }
-
-**bus** - the numerical identifier of the CAN bus where this request should be
- sent, most likely 1 or 2 (for a vehicle interface with 2 CAN controllers).
-
-**id** - the CAN arbitration ID for the request.
-
-**mode** - the OBD-II mode of the request - 1 through 15 (1 through 9 are the
- standardized modes).
-
-**pid** - (optional) the PID for the request, if applicable.
-
-**payload** - (optional) up to 7 bytes of data for the request's payload
- represented as a hexidecimal number in a string. Many JSON parser cannot
- handle 64-bit integers, which is why we are not using a numerical data type.
-
-**parse_payload** - (optional, false by default) if true, the complete payload in the
- response message will be parsed as a number and returned in the 'value' field of
- the response. The 'payload' field will be omitted in responses with a
- 'value'.
-
-**multiple_response** - (optional, false by default) if true, request will stay
- active for a full 100ms, even after receiving a diagnostic response message.
- This is useful for requests to the functional broadcast arbitration ID
- (`0x7df`) when you need to get responses from multiple modules. It's possible
- to set this to `true` for non-broadcast requests, but in practice you won't
- see any additional responses after the first and it will just take up memory
- in the VI for longer.
-
-**factor** - (optional, 1.0 by default) if `parse_payload` is true, the value in
- the payload will be multiplied by this factor before returning. The `factor`
- is applied before the `offset`.
-
-**offset** - (optional, 0 by default) if `parse_payload` is true, this offset
- will be added to the value in the payload before returning. The `offset` is
- applied after the `factor`.
-
-**frequency** - (optional, defaults to 0) The frequency in Hz to send this
- request. To send a single request, set this to 0 or leave it out.
-
-**name** - (optional, defaults to nothing) A human readable, string name for
- this request. If provided, the response will have a `name` field (much like a
- normal translated message) in place of the request details (i.e. the bus,
- id, mode and pid). TODO elaborate on this.
-
-The `bus+id+mode+pid` key is unique, so if you send a create request with that
-key twice, it'll overwrite the existing one (i.e. it will change the frequency,
-the only other parameter). To cancel a recurring request, send this command with
-the frequency set to 0.
-
-TODO it'd be nice to have the OBD-II PIDs built in, with the proper conversion
-functions - that may need a different output format
-
-If you're just requesting a PID, you can use this minimal field set for the
-`request` object:
-
- {"bus": 1, "id": 1234, "mode": 1, "pid": 5}
-
-### Responses
-
- {"bus": 1,
- "id": 1234,
- "mode": 1,
- "pid": 5,
- "success": true,
- "negative_response_code": 17,
- "payload": "0x1234",
- "parsed_payload": 4660}