This is the description of the MQTT API bindings for the Tilt Bricklet. General information and technical specifications for the Tilt Bricklet are summarized in its hardware description.
An installation guide for the MQTT API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
1 2 3 4 5 6 | # Change XYZ to the UID of your Tilt Bricklet
setup:
# Get current tilt state
subscribe to tinkerforge/response/tilt_bricklet/XYZ/get_tilt_state
publish '' to tinkerforge/request/tilt_bricklet/XYZ/get_tilt_state
|
Download (example-callback.txt)
1 2 3 4 5 6 7 8 9 | # Change XYZ to the UID of your Tilt Bricklet
setup:
# Enable tilt state callback
publish '' to tinkerforge/request/tilt_bricklet/XYZ/enable_tilt_state_callback
# Handle incoming tilt state callbacks
subscribe to tinkerforge/callback/tilt_bricklet/XYZ/tilt_state
publish '{"register": true}' to tinkerforge/register/tilt_bricklet/XYZ/tilt_state # Register tilt_state callback
|
All published payloads to and from the MQTT bindings are in JSON format.
If an error occures, the bindings publish a JSON object containing the error message as member _ERROR
.
It is published on the corresponding response topic: .../response/...
for .../request/...
and .../callback/...
for .../register/...
.
request/
tilt_bricklet/
<UID>/
get_tilt_state
¶Request: |
|
---|---|
Response: |
|
Returns the current tilt state. The state can either be
The following symbols are available for this function:
For state:
request/
tilt_bricklet/
<UID>/
get_identity
¶Request: |
|
---|---|
Response: |
|
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.
The device identifier numbers can be found here. If symbolic output is not disabled, the device identifier is mapped to the corresponding name in the format used in topics.
The display name contains the Tilt's name in a human readable form.
request/
tilt_bricklet/
<UID>/
enable_tilt_state_callback
¶Request: |
|
---|---|
Response: |
|
Enables the register/tilt_bricklet/<UID>/tilt_state
callback.
request/
tilt_bricklet/
<UID>/
disable_tilt_state_callback
¶Request: |
|
---|---|
Response: |
|
Disables the register/tilt_bricklet/<UID>/tilt_state
callback.
request/
tilt_bricklet/
<UID>/
is_tilt_state_callback_enabled
¶Request: |
|
---|---|
Response: |
|
Returns true if the register/tilt_bricklet/<UID>/tilt_state
callback is enabled.
Callbacks can be registered to receive
time critical or recurring data from the device. The registration is done
with the corresponding .../register/...
topic and an optional suffix.
This suffix can be used to deregister the callback later.
Note
Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.
register/
tilt_bricklet/
<UID>/
tilt_state
¶Register Request: |
|
---|---|
Callback Response: |
|
A callback can be registered for this event by publishing to the .../register/tilt_bricklet/<UID>/tilt_state[/<SUFFIX>]
topic with the payload "true".
An added callback can be removed by publishing to the same topic with the payload "false".
To support multiple (de)registrations, e.g. for message filtering, an optional suffix can be used.
If the callback is triggered, a message with it's payload is published under the corresponding .../callback/tilt_bricklet/<UID>/tilt_state[/<SUFFIX>]
topic for each registered suffix.
This callback provides the current tilt state. It is called every time the state changes.
See request/tilt_bricklet/<UID>/get_tilt_state
for a description of the states.
The following symbols are available for this function:
For state: