Shell - Voltage/Current Bricklet 2.0

This is the description of the Shell API bindings for the Voltage/Current Bricklet 2.0. General information and technical specifications for the Voltage/Current Bricklet 2.0 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 2.0

# Get current voltage
tinkerforge call voltage-current-v2-bricklet $uid get-voltage

# Get current current
tinkerforge call voltage-current-v2-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 2.0

# Handle incoming current callbacks
tinkerforge dispatch voltage-current-v2-bricklet $uid current &

# Set period for current callback to 1s (1000ms) without a threshold
tinkerforge call voltage-current-v2-bricklet $uid set-current-callback-configuration 1000 false threshold-option-off 0 0

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 2.0

# Handle incoming power callbacks
tinkerforge dispatch voltage-current-v2-bricklet $uid power &

# Configure threshold for power "greater than 10 W"
# with a debounce period of 1s (1000ms)
tinkerforge call voltage-current-v2-bricklet $uid set-power-callback-configuration 1000 false 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-v2-bricklet [<option>..] <uid> <function> [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The call command is used to call a function of the Voltage/Current Bricklet 2.0. 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 2.0 and exits
tinkerforge dispatch voltage-current-v2-bricklet [<option>..] <uid> <callback>
Parameters:
  • <uid> -- string
  • <callback> -- string

The dispatch command is used to dispatch a callback of the Voltage/Current Bricklet 2.0. 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 2.0 and exits
tinkerforge call voltage-current-v2-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-v2-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-v2-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 value periodically, it is recommended to use the current callback. You can set the callback configuration with set-current-callback-configuration.

tinkerforge call voltage-current-v2-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 value periodically, it is recommended to use the voltage callback. You can set the callback configuration with set-voltage-callback-configuration.

tinkerforge call voltage-current-v2-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 value periodically, it is recommended to use the power callback. You can set the callback configuration with set-power-callback-configuration.

tinkerforge call voltage-current-v2-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 2.0. 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-v2-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-v2-bricklet <uid> set-calibration <voltage-multiplier> <voltage-divisor> <current-multiplier> <current-divisor>
Parameters:
  • <voltage-multiplier> -- int
  • <voltage-divisor> -- int
  • <current-multiplier> -- int
  • <current-divisor> -- int
Output:

no output

Since the ADC and the shunt resistor used for the measurements are not perfect they need to be calibrated by a multiplier and a divisor if a very precise reading is needed.

For example, if you are expecting a current of 1000mA and you are measuring 1023mA, you can calibrate the Voltage/Current Bricklet by setting the current multiplier to 1000 and the divisor to 1023. The same applies for the voltage.

tinkerforge call voltage-current-v2-bricklet <uid> get-calibration
Output:
  • voltage-multiplier -- int
  • voltage-divisor -- int
  • current-multiplier -- int
  • current-divisor -- int

Returns the calibration as set by set-calibration.

tinkerforge call voltage-current-v2-bricklet <uid> get-spitfp-error-count
Output:
  • error-count-ack-checksum -- int
  • error-count-message-checksum -- int
  • error-count-frame -- int
  • error-count-overflow -- int

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,
  • message checksum errors,
  • framing errors and
  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

tinkerforge call voltage-current-v2-bricklet <uid> set-bootloader-mode <mode>
Parameters:
  • <mode> -- int (has symbols)
Output:
  • status -- int (has symbols)

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following symbols are available for this function:

  • bootloader-mode-bootloader = 0, for <mode>
  • bootloader-mode-firmware = 1, for <mode>
  • bootloader-mode-bootloader-wait-for-reboot = 2, for <mode>
  • bootloader-mode-firmware-wait-for-reboot = 3, for <mode>
  • bootloader-mode-firmware-wait-for-erase-and-reboot = 4, for <mode>
  • bootloader-status-ok = 0, for status
  • bootloader-status-invalid-mode = 1, for status
  • bootloader-status-no-change = 2, for status
  • bootloader-status-entry-function-not-present = 3, for status
  • bootloader-status-device-identifier-incorrect = 4, for status
  • bootloader-status-crc-mismatch = 5, for status
tinkerforge call voltage-current-v2-bricklet <uid> get-bootloader-mode
Output:
  • mode -- int (has symbols)

Returns the current bootloader mode, see set-bootloader-mode.

The following symbols are available for this function:

  • bootloader-mode-bootloader = 0, for mode
  • bootloader-mode-firmware = 1, for mode
  • bootloader-mode-bootloader-wait-for-reboot = 2, for mode
  • bootloader-mode-firmware-wait-for-reboot = 3, for mode
  • bootloader-mode-firmware-wait-for-erase-and-reboot = 4, for mode
tinkerforge call voltage-current-v2-bricklet <uid> set-write-firmware-pointer <pointer>
Parameters:
  • <pointer> -- int
Output:

no output

Sets the firmware pointer for write-firmware. The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

tinkerforge call voltage-current-v2-bricklet <uid> write-firmware <data>
Parameters:
  • <data> -- int,int,..61x..,int
Output:
  • status -- int

Writes 64 Bytes of firmware at the position as written by set-write-firmware-pointer before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

tinkerforge call voltage-current-v2-bricklet <uid> set-status-led-config <config>
Parameters:
  • <config> -- int (has symbols)
Output:

no output

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following symbols are available for this function:

  • status-led-config-off = 0, for <config>
  • status-led-config-on = 1, for <config>
  • status-led-config-show-heartbeat = 2, for <config>
  • status-led-config-show-status = 3, for <config>
tinkerforge call voltage-current-v2-bricklet <uid> get-status-led-config
Output:
  • config -- int (has symbols)

Returns the configuration as set by set-status-led-config

The following symbols are available for this function:

  • status-led-config-off = 0, for config
  • status-led-config-on = 1, for config
  • status-led-config-show-heartbeat = 2, for config
  • status-led-config-show-status = 3, for config
tinkerforge call voltage-current-v2-bricklet <uid> get-chip-temperature
Output:
  • temperature -- int

Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

tinkerforge call voltage-current-v2-bricklet <uid> reset
Output:no output

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

tinkerforge call voltage-current-v2-bricklet <uid> write-uid <uid>
Parameters:
  • <uid> -- int
Output:

no output

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

tinkerforge call voltage-current-v2-bricklet <uid> read-uid
Output:
  • uid -- int

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

tinkerforge call voltage-current-v2-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-v2-bricklet <uid> set-current-callback-configuration <period> <value-has-to-change> <option> <min> <max>
Parameters:
  • <period> -- int
  • <value-has-to-change> -- bool
  • <option> -- char (has symbols)
  • <min> -- int
  • <max> -- int
Output:

no output

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

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the current callback.

The following options are possible:

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

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The default value is (0, false, '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-v2-bricklet <uid> get-current-callback-configuration
Output:
  • period -- int
  • value-has-to-change -- bool
  • option -- char (has symbols)
  • min -- int
  • max -- int

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

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-v2-bricklet <uid> set-voltage-callback-configuration <period> <value-has-to-change> <option> <min> <max>
Parameters:
  • <period> -- int
  • <value-has-to-change> -- bool
  • <option> -- char (has symbols)
  • <min> -- int
  • <max> -- int
Output:

no output

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

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the voltage callback.

The following options are possible:

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

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The default value is (0, false, '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-v2-bricklet <uid> get-voltage-callback-configuration
Output:
  • period -- int
  • value-has-to-change -- bool
  • option -- char (has symbols)
  • min -- int
  • max -- int

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

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-v2-bricklet <uid> set-power-callback-configuration <period> <value-has-to-change> <option> <min> <max>
Parameters:
  • <period> -- int
  • <value-has-to-change> -- bool
  • <option> -- char (has symbols)
  • <min> -- int
  • <max> -- int
Output:

no output

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

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the power callback.

The following options are possible:

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

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The default value is (0, false, '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-v2-bricklet <uid> get-power-callback-configuration
Output:
  • period -- int
  • value-has-to-change -- bool
  • option -- char (has symbols)
  • min -- int
  • max -- int

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

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

Callbacks

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

tinkerforge dispatch voltage-current-v2-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-v2-bricklet <uid> current
Output:
  • current -- int

This callback is triggered periodically according to the configuration set by set-current-callback-configuration.

The parameter is the same as get-current.

tinkerforge dispatch voltage-current-v2-bricklet <uid> voltage
Output:
  • voltage -- int

This callback is triggered periodically according to the configuration set by set-voltage-callback-configuration.

The parameter is the same as get-voltage.

tinkerforge dispatch voltage-current-v2-bricklet <uid> power
Output:
  • power -- int

This callback is triggered periodically according to the configuration set by set-power-callback-configuration.

The parameter is the same as get-power.