This is the description of the MQTT API bindings for the Industrial Dual Analog In Bricklet. General information and technical specifications for the Industrial Dual Analog In 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 Industrial Dual Analog In Bricklet
setup:
# Get current voltage from channel 1
subscribe to tinkerforge/response/industrial_dual_analog_in_bricklet/XYZ/get_voltage
publish '{"channel": 1}' to tinkerforge/request/industrial_dual_analog_in_bricklet/XYZ/get_voltage
|
Download (example-callback.txt)
1 2 3 4 5 6 7 8 9 10 11 | # Change XYZ to the UID of your Industrial Dual Analog In Bricklet
setup:
# Handle incoming voltage callbacks
subscribe to tinkerforge/callback/industrial_dual_analog_in_bricklet/XYZ/voltage
publish '{"register": true}' to tinkerforge/register/industrial_dual_analog_in_bricklet/XYZ/voltage # Register voltage callback
# Set period for voltage (channel 1) callback to 1s (1000ms)
# Note: The voltage (channel 1) callback is only called every second
# if the voltage (channel 1) has changed since the last call!
publish '{"channel": 1, "period": 1000}' to tinkerforge/request/industrial_dual_analog_in_bricklet/XYZ/set_voltage_callback_period
|
Download (example-threshold.txt)
1 2 3 4 5 6 7 8 9 10 11 12 | # Change XYZ to the UID of your Industrial Dual Analog In Bricklet
setup:
# Get threshold callbacks with a debounce time of 10 seconds (10000ms)
publish '{"debounce": 10000}' to tinkerforge/request/industrial_dual_analog_in_bricklet/XYZ/set_debounce_period
# Handle incoming voltage reached callbacks
subscribe to tinkerforge/callback/industrial_dual_analog_in_bricklet/XYZ/voltage_reached
publish '{"register": true}' to tinkerforge/register/industrial_dual_analog_in_bricklet/XYZ/voltage_reached # Register voltage_reached callback
# Configure threshold for voltage (channel 1) "greater than 10 V"
publish '{"channel": 1, "option": "greater", "min": 10000, "max": 0}' to tinkerforge/request/industrial_dual_analog_in_bricklet/XYZ/set_voltage_callback_threshold
|
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/
industrial_dual_analog_in_bricklet/
<UID>/
get_voltage
¶Request: |
|
---|---|
Response: |
|
Returns the voltage for the given channel.
If you want to get the voltage periodically, it is recommended to use the
register/industrial_dual_analog_in_bricklet/<UID>/voltage
callback and set the period with
request/industrial_dual_analog_in_bricklet/<UID>/set_voltage_callback_period
.
request/
industrial_dual_analog_in_bricklet/
<UID>/
set_sample_rate
¶Request: |
|
---|---|
Response: |
|
Sets the sample rate. The sample rate can be between 1 sample per second and 976 samples per second. Decreasing the sample rate will also decrease the noise on the data.
The following symbols are available for this function:
For rate:
request/
industrial_dual_analog_in_bricklet/
<UID>/
get_sample_rate
¶Request: |
|
---|---|
Response: |
|
Returns the sample rate as set by request/industrial_dual_analog_in_bricklet/<UID>/set_sample_rate
.
The following symbols are available for this function:
For rate:
request/
industrial_dual_analog_in_bricklet/
<UID>/
set_calibration
¶Request: |
|
---|---|
Response: |
|
Sets offset and gain of MCP3911 internal calibration registers.
See MCP3911 datasheet 7.7 and 7.8. The Industrial Dual Analog In Bricklet is already factory calibrated by Tinkerforge. It should not be necessary for you to use this function
request/
industrial_dual_analog_in_bricklet/
<UID>/
get_calibration
¶Request: |
|
---|---|
Response: |
|
Returns the calibration as set by request/industrial_dual_analog_in_bricklet/<UID>/set_calibration
.
request/
industrial_dual_analog_in_bricklet/
<UID>/
get_adc_values
¶Request: |
|
---|---|
Response: |
|
Returns the ADC values as given by the MCP3911 IC. This function
is needed for proper calibration, see request/industrial_dual_analog_in_bricklet/<UID>/set_calibration
.
request/
industrial_dual_analog_in_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 Industrial Dual Analog In's name in a human readable form.
request/
industrial_dual_analog_in_bricklet/
<UID>/
set_voltage_callback_period
¶Request: |
|
---|---|
Response: |
|
Sets the period with which the register/industrial_dual_analog_in_bricklet/<UID>/voltage
callback is triggered
periodically for the given channel. A value of 0 turns the callback off.
The register/industrial_dual_analog_in_bricklet/<UID>/voltage
callback is only triggered if the voltage has changed since the
last triggering.
request/
industrial_dual_analog_in_bricklet/
<UID>/
get_voltage_callback_period
¶Request: |
|
---|---|
Response: |
|
Returns the period as set by request/industrial_dual_analog_in_bricklet/<UID>/set_voltage_callback_period
.
request/
industrial_dual_analog_in_bricklet/
<UID>/
set_voltage_callback_threshold
¶Request: |
|
---|---|
Response: |
|
Sets the thresholds for the register/industrial_dual_analog_in_bricklet/<UID>/voltage_reached
callback for the given
channel.
The following options are possible:
Option | Description |
---|---|
'x' | Callback is turned off |
'o' | Callback is triggered when the voltage is outside the min and max values |
'i' | Callback is triggered when the voltage is inside the min and max values |
'<' | Callback is triggered when the voltage is smaller than the min value (max is ignored) |
'>' | Callback is triggered when the voltage is greater than the min value (max is ignored) |
The following symbols are available for this function:
For option:
request/
industrial_dual_analog_in_bricklet/
<UID>/
get_voltage_callback_threshold
¶Request: |
|
---|---|
Response: |
|
Returns the threshold as set by request/industrial_dual_analog_in_bricklet/<UID>/set_voltage_callback_threshold
.
The following symbols are available for this function:
For option:
request/
industrial_dual_analog_in_bricklet/
<UID>/
set_debounce_period
¶Request: |
|
---|---|
Response: |
|
Sets the period with which the threshold callback
is triggered, if the threshold
keeps being reached.
request/
industrial_dual_analog_in_bricklet/
<UID>/
get_debounce_period
¶Request: |
|
---|---|
Response: |
|
Returns the debounce period as set by request/industrial_dual_analog_in_bricklet/<UID>/set_debounce_period
.
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/
industrial_dual_analog_in_bricklet/
<UID>/
voltage
¶Register Request: |
|
---|---|
Callback Response: |
|
A callback can be registered for this event by publishing to the .../register/industrial_dual_analog_in_bricklet/<UID>/voltage[/<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/industrial_dual_analog_in_bricklet/<UID>/voltage[/<SUFFIX>]
topic for each registered suffix.
This callback is triggered periodically with the period that is set by
request/industrial_dual_analog_in_bricklet/<UID>/set_voltage_callback_period
. The callback payload is the voltage of the
channel.
The register/industrial_dual_analog_in_bricklet/<UID>/voltage
callback is only triggered if the voltage has changed since the
last triggering.
register/
industrial_dual_analog_in_bricklet/
<UID>/
voltage_reached
¶Register Request: |
|
---|---|
Callback Response: |
|
A callback can be registered for this event by publishing to the .../register/industrial_dual_analog_in_bricklet/<UID>/voltage_reached[/<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/industrial_dual_analog_in_bricklet/<UID>/voltage_reached[/<SUFFIX>]
topic for each registered suffix.
This callback is triggered when the threshold as set by
request/industrial_dual_analog_in_bricklet/<UID>/set_voltage_callback_threshold
is reached.
The callback payload is the voltage of the channel.
If the threshold keeps being reached, the callback is triggered periodically
with the period as set by request/industrial_dual_analog_in_bricklet/<UID>/set_debounce_period
.