Shell - Voltage/Current Bricklet

This is the description of the Shell API bindings for the Voltage/Current Bricklet. General information and technical specifications for the Voltage/Current Bricklet are summarized in its hardware description.

An installation guide for the Shell API bindings is part of their general description.

Examples

The example code below is Public Domain (CC0 1.0).

Simple

Download (example-simple.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Voltage/Current Bricklet

# Get current voltage
tinkerforge call voltage-current-bricklet $uid get-voltage

# Get current current
tinkerforge call voltage-current-bricklet $uid get-current

Callback

Download (example-callback.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Voltage/Current Bricklet

# Handle incoming current callbacks
tinkerforge dispatch voltage-current-bricklet $uid current &

# Set period for current callback to 1s (1000ms)
# Note: The current callback is only called every second
#       if the current has changed since the last call!
tinkerforge call voltage-current-bricklet $uid set-current-callback-period 1000

echo "Press key to exit"; read dummy

kill -- -$$ # Stop callback dispatch in background

Threshold

Download (example-threshold.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Voltage/Current Bricklet

# Get threshold callbacks with a debounce time of 10 seconds (10000ms)
tinkerforge call voltage-current-bricklet $uid set-debounce-period 10000

# Handle incoming power reached callbacks
tinkerforge dispatch voltage-current-bricklet $uid power-reached &

# Configure threshold for power "greater than 10 W"
tinkerforge call voltage-current-bricklet $uid set-power-callback-threshold threshold-option-greater 10000 0

echo "Press key to exit"; read dummy

kill -- -$$ # Stop callback dispatch in background

API

Possible exit codes for all tinkerforge commands are:

  • 1: interrupted (ctrl+c)
  • 2: syntax error
  • 21: Python 2.5 or newer is required
  • 22: Python argparse module is missing
  • 23: socket error
  • 24: other exception
  • 25: invalid placeholder in format string
  • 26: authentication error
  • 201: timeout occurred
  • 209: invalid argument value
  • 210: function is not supported
  • 211: unknown error

Command Structure

The common options of the call and dispatch commands are documented here. The specific command structure is shown below.

tinkerforge call voltage-current-bricklet [<option>..] <uid> <function> [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The call command is used to call a function of the Voltage/Current Bricklet. It can take several options:

  • --help shows help for the specific call command and exits
  • --list-functions shows a list of known functions of the Voltage/Current Bricklet and exits
tinkerforge dispatch voltage-current-bricklet [<option>..] <uid> <callback>
Parameters:
  • <uid> -- string
  • <callback> -- string

The dispatch command is used to dispatch a callback of the Voltage/Current Bricklet. It can take several options:

  • --help shows help for the specific dispatch command and exits
  • --list-callbacks shows a list of known callbacks of the Voltage/Current Bricklet and exits
tinkerforge call voltage-current-bricklet <uid> <function> [<option>..] [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The <function> to be called can take different options depending of its kind. All functions can take the following options:

  • --help shows help for the specific function and exits

Getter functions can take the following options:

  • --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Setter functions can take the following options:

  • --expect-response requests response and waits for it

The --expect-response option for setter functions allows to detect timeouts and other error conditions calls of setters as well. The device will then send a response for this purpose. If this option is not given for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

tinkerforge dispatch voltage-current-bricklet <uid> <callback> [<option>..]
Parameters:
  • <uid> -- string
  • <callback> -- string

The <callback> to be dispatched can take several options:

  • --help shows help for the specific callback and exits
  • --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Basic Functions

tinkerforge call voltage-current-bricklet <uid> get-current
Output:
  • current -- int

Returns the current. The value is in mA and between -20000mA and 20000mA.

If you want to get the current periodically, it is recommended to use the current callback and set the period with set-current-callback-period.

tinkerforge call voltage-current-bricklet <uid> get-voltage
Output:
  • voltage -- int

Returns the voltage. The value is in mV and between 0mV and 36000mV.

If you want to get the voltage periodically, it is recommended to use the voltage callback and set the period with set-voltage-callback-period.

tinkerforge call voltage-current-bricklet <uid> get-power
Output:
  • power -- int

Returns the power. The value is in mW and between 0mV and 720000mW.

If you want to get the power periodically, it is recommended to use the power callback and set the period with set-power-callback-period.

tinkerforge call voltage-current-bricklet <uid> set-configuration <averaging> <voltage-conversion-time> <current-conversion-time>
Parameters:
  • <averaging> -- int (has symbols)
  • <voltage-conversion-time> -- int
  • <current-conversion-time> -- int
Output:

no output

Sets the configuration of the Voltage/Current Bricklet. It is possible to configure number of averages as well as voltage and current conversion time.

Averaging:

Value Number of Averages
0 1
1 4
2 16
3 64
4 128
5 256
6 512
>=7 1024

Voltage/Current conversion:

Value Conversion time
0 140µs
1 204µs
2 332µs
3 588µs
4 1.1ms
5 2.116ms
6 4.156ms
>=7 8.244ms

The default values are 3, 4 and 4 (64, 1.1ms, 1.1ms) for averaging, voltage conversion and current conversion.

The following symbols are available for this function:

  • averaging-1 = 0, for <averaging>
  • averaging-4 = 1, for <averaging>
  • averaging-16 = 2, for <averaging>
  • averaging-64 = 3, for <averaging>
  • averaging-128 = 4, for <averaging>
  • averaging-256 = 5, for <averaging>
  • averaging-512 = 6, for <averaging>
  • averaging-1024 = 7, for <averaging>
tinkerforge call voltage-current-bricklet <uid> get-configuration
Output:
  • averaging -- int (has symbols)
  • voltage-conversion-time -- int
  • current-conversion-time -- int

Returns the configuration as set by set-configuration.

The following symbols are available for this function:

  • averaging-1 = 0, for averaging
  • averaging-4 = 1, for averaging
  • averaging-16 = 2, for averaging
  • averaging-64 = 3, for averaging
  • averaging-128 = 4, for averaging
  • averaging-256 = 5, for averaging
  • averaging-512 = 6, for averaging
  • averaging-1024 = 7, for averaging

Advanced Functions

tinkerforge call voltage-current-bricklet <uid> set-calibration <gain-multiplier> <gain-divisor>
Parameters:
  • <gain-multiplier> -- int
  • <gain-divisor> -- int
Output:

no output

Since the shunt resistor that is used to measure the current is not perfectly precise, it needs to be calibrated by a multiplier and divisor if a very precise reading is needed.

For example, if you are expecting a measurement of 1000mA and you are measuring 1023mA, you can calibrate the Voltage/Current Bricklet by setting the multiplier to 1000 and the divisor to 1023.

tinkerforge call voltage-current-bricklet <uid> get-calibration
Output:
  • gain-multiplier -- int
  • gain-divisor -- int

Returns the calibration as set by set-calibration.

tinkerforge call voltage-current-bricklet <uid> get-identity
Output:
  • uid -- string
  • connected-uid -- string
  • position -- char
  • hardware-version -- int,int,int
  • firmware-version -- int,int,int
  • device-identifier -- int (has symbols)

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' or 'd'.

The device identifier numbers can be found here

Callback Configuration Functions

tinkerforge call voltage-current-bricklet <uid> set-current-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms with which the current callback is triggered periodically. A value of 0 turns the callback off.

The current callback is only triggered if the current has changed since the last triggering.

The default value is 0.

tinkerforge call voltage-current-bricklet <uid> get-current-callback-period
Output:
  • period -- int

Returns the period as set by set-current-callback-period.

tinkerforge call voltage-current-bricklet <uid> set-voltage-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms with which the voltage callback is triggered periodically. A value of 0 turns the callback off.

The voltage callback is only triggered if the voltage has changed since the last triggering.

The default value is 0.

tinkerforge call voltage-current-bricklet <uid> get-voltage-callback-period
Output:
  • period -- int

Returns the period as set by set-voltage-callback-period.

tinkerforge call voltage-current-bricklet <uid> set-power-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

Sets the period in ms with which the power callback is triggered periodically. A value of 0 turns the callback off.

The power callback is only triggered if the power has changed since the last triggering.

The default value is 0.

tinkerforge call voltage-current-bricklet <uid> get-power-callback-period
Output:
  • period -- int

Returns the period as set by get-power-callback-period.

tinkerforge call voltage-current-bricklet <uid> set-current-callback-threshold <option> <min> <max>
Parameters:
  • <option> -- char (has symbols)
  • <min> -- int
  • <max> -- int
Output:

no output

Sets the thresholds for the current-reached callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the current is outside the min and max values
'i' Callback is triggered when the current is inside the min and max values
'<' Callback is triggered when the current is smaller than the min value (max is ignored)
'>' Callback is triggered when the current is greater than the min value (max is ignored)

The default value is ('x', 0, 0).

The following symbols are available for this function:

  • threshold-option-off = x, for <option>
  • threshold-option-outside = o, for <option>
  • threshold-option-inside = i, for <option>
  • threshold-option-smaller = <, for <option>
  • threshold-option-greater = >, for <option>
tinkerforge call voltage-current-bricklet <uid> get-current-callback-threshold
Output:
  • option -- char (has symbols)
  • min -- int
  • max -- int

Returns the threshold as set by set-current-callback-threshold.

The following symbols are available for this function:

  • threshold-option-off = x, for option
  • threshold-option-outside = o, for option
  • threshold-option-inside = i, for option
  • threshold-option-smaller = <, for option
  • threshold-option-greater = >, for option
tinkerforge call voltage-current-bricklet <uid> set-voltage-callback-threshold <option> <min> <max>
Parameters:
  • <option> -- char (has symbols)
  • <min> -- int
  • <max> -- int
Output:

no output

Sets the thresholds for the voltage-reached callback.

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 default value is ('x', 0, 0).

The following symbols are available for this function:

  • threshold-option-off = x, for <option>
  • threshold-option-outside = o, for <option>
  • threshold-option-inside = i, for <option>
  • threshold-option-smaller = <, for <option>
  • threshold-option-greater = >, for <option>
tinkerforge call voltage-current-bricklet <uid> get-voltage-callback-threshold
Output:
  • option -- char (has symbols)
  • min -- int
  • max -- int

Returns the threshold as set by set-voltage-callback-threshold.

The following symbols are available for this function:

  • threshold-option-off = x, for option
  • threshold-option-outside = o, for option
  • threshold-option-inside = i, for option
  • threshold-option-smaller = <, for option
  • threshold-option-greater = >, for option
tinkerforge call voltage-current-bricklet <uid> set-power-callback-threshold <option> <min> <max>
Parameters:
  • <option> -- char (has symbols)
  • <min> -- int
  • <max> -- int
Output:

no output

Sets the thresholds for the power-reached callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the power is outside the min and max values
'i' Callback is triggered when the power is inside the min and max values
'<' Callback is triggered when the power is smaller than the min value (max is ignored)
'>' Callback is triggered when the power is greater than the min value (max is ignored)

The default value is ('x', 0, 0).

The following symbols are available for this function:

  • threshold-option-off = x, for <option>
  • threshold-option-outside = o, for <option>
  • threshold-option-inside = i, for <option>
  • threshold-option-smaller = <, for <option>
  • threshold-option-greater = >, for <option>
tinkerforge call voltage-current-bricklet <uid> get-power-callback-threshold
Output:
  • option -- char (has symbols)
  • min -- int
  • max -- int

Returns the threshold as set by set-power-callback-threshold.

The following symbols are available for this function:

  • threshold-option-off = x, for option
  • threshold-option-outside = o, for option
  • threshold-option-inside = i, for option
  • threshold-option-smaller = <, for option
  • threshold-option-greater = >, for option
tinkerforge call voltage-current-bricklet <uid> set-debounce-period <debounce>
Parameters:
  • <debounce> -- int
Output:

no output

Sets the period in ms with which the threshold callbacks

are triggered, if the thresholds

keep being reached.

The default value is 100.

tinkerforge call voltage-current-bricklet <uid> get-debounce-period
Output:
  • debounce -- int

Returns the debounce period as set by set-debounce-period.

Callbacks

Callbacks can be used to receive time critical or recurring data from the device:

tinkerforge dispatch voltage-current-bricklet <uid> example

The available callbacks are described below.

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.

tinkerforge dispatch voltage-current-bricklet <uid> current
Output:
  • current -- int

This callback is triggered periodically with the period that is set by set-current-callback-period. The parameter is the current of the sensor.

The current callback is only triggered if the current has changed since the last triggering.

tinkerforge dispatch voltage-current-bricklet <uid> voltage
Output:
  • voltage -- int

This callback is triggered periodically with the period that is set by set-voltage-callback-period. The parameter is the voltage of the sensor.

The voltage callback is only triggered if the voltage has changed since the last triggering.

tinkerforge dispatch voltage-current-bricklet <uid> power
Output:
  • power -- int

This callback is triggered periodically with the period that is set by set-power-callback-period. The parameter is the power of the sensor.

The power callback is only triggered if the power has changed since the last triggering.

tinkerforge dispatch voltage-current-bricklet <uid> current-reached
Output:
  • current -- int

This callback is triggered when the threshold as set by set-current-callback-threshold is reached. The parameter is the current of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by set-debounce-period.

tinkerforge dispatch voltage-current-bricklet <uid> voltage-reached
Output:
  • voltage -- int

This callback is triggered when the threshold as set by set-voltage-callback-threshold is reached. The parameter is the voltage of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by set-debounce-period.

tinkerforge dispatch voltage-current-bricklet <uid> power-reached
Output:
  • power -- int

This callback is triggered when the threshold as set by set-power-callback-threshold is reached. The parameter is the power of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by set-debounce-period.