Shell - DC Bricklet 2.0¶

Configuration¶

Download (example-configuration.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 DC Bricklet 2.0

tinkerforge call dc-v2-bricklet $uid set-drive-mode drive-mode-drive-coast
tinkerforge call dc-v2-bricklet $uid set-pwm-frequency 10000 # Use PWM frequency of 10 kHz
tinkerforge call dc-v2-bricklet $uid set-motion 4096 16384 # Slow acceleration (12.5 %/s), fast decceleration (50 %/s) for stopping
tinkerforge call dc-v2-bricklet $uid set-velocity 32767 # Full speed forward (100 %)
tinkerforge call dc-v2-bricklet $uid set-enabled true # Enable motor power

echo "Press key to exit"; read dummy

tinkerforge call dc-v2-bricklet $uid set-velocity 0 # Stop motor before disabling motor power
sleep 2 # Wait for motor to actually stop: velocity (100 %) / decceleration (50 %/s) = 2 s
tinkerforge call dc-v2-bricklet $uid set-enabled false # Disable motor power

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 DC Bricklet 2.0

# The acceleration has to be smaller or equal to the maximum
# acceleration of the DC motor, otherwise the velocity reached
# callback will be called too early
tinkerforge call dc-v2-bricklet $uid set-motion 4096 16384 # Slow acceleration (12.5 %/s), fast decceleration (50 %/s) for stopping
tinkerforge call dc-v2-bricklet $uid set-velocity 32767 # Full speed forward (100 %)

# Use velocity reached callback to swing back and forth
# between full speed forward and full speed backward
tinkerforge dispatch dc-v2-bricklet $uid velocity-reached\
 --execute "if   [ {velocity} -eq  32767 ]; then tinkerforge call dc-v2-bricklet $uid set-velocity -32767;
            elif [ {velocity} -eq -32767 ]; then tinkerforge call dc-v2-bricklet $uid set-velocity  32767;
            else echo error; fi" &

# Enable motor power
tinkerforge call dc-v2-bricklet $uid set-enabled true

echo "Press key to exit"; read dummy

tinkerforge call dc-v2-bricklet $uid set-velocity 0 # Stop motor before disabling motor power
sleep 2 # Wait for motor to actually stop: velocity (100 %) / decceleration (50 %/s) = 2 s
tinkerforge call dc-v2-bricklet $uid set-enabled false # Disable motor power

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

Command Structure¶

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

tinkerforge call dc-v2-bricklet [<option>..] <uid> <function> [<argument>..]¶

Parameters:	<uid> – Type: String <function> – Type: String

The call command is used to call a function of the DC 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 DC Bricklet 2.0 and exits

tinkerforge dispatch dc-v2-bricklet [<option>..] <uid> <callback>¶

Parameters:	<uid> – Type: String <callback> – Type: String

The dispatch command is used to dispatch a callback of the DC 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 DC Bricklet 2.0 and exits

tinkerforge call dc-v2-bricklet <uid> <function> [<option>..] [<argument>..]¶

Parameters:	<uid> – Type: String <function> – Type: 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 sent and errors are silently ignored, because they cannot be detected.

tinkerforge dispatch dc-v2-bricklet <uid> <callback> [<option>..]¶

Parameters:	<uid> – Type: String <callback> – Type: 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 dc-v2-bricklet <uid> set-enabled <enabled>¶

Parameters:	<enabled> – Type: Bool
Output:	no output

Enables/Disables the driver chip. The driver parameters can be configured (velocity, acceleration, etc) before it is enabled.

tinkerforge call dc-v2-bricklet <uid> get-enabled¶

Output:	enabled – Type: Bool, Default: false

Returns true if the driver chip is enabled, false otherwise.

tinkerforge call dc-v2-bricklet <uid> set-velocity <velocity>¶

Parameters:	<velocity> – Type: Int, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1], Default: 0
Output:	no output

Sets the velocity of the motor. Whereas -32767 is full speed backward, 0 is stop and 32767 is full speed forward. Depending on the acceleration (see set-motion), the motor is not immediately brought to the velocity but smoothly accelerated.

The velocity describes the duty cycle of the PWM with which the motor is controlled, e.g. a velocity of 3277 sets a PWM with a 10% duty cycle. You can not only control the duty cycle of the PWM but also the frequency, see set-pwm-frequency.

tinkerforge call dc-v2-bricklet <uid> get-velocity¶

Output:	velocity – Type: Int, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1], Default: 0

Returns the velocity as set by set-velocity.

tinkerforge call dc-v2-bricklet <uid> get-current-velocity¶

Output:	velocity – Type: Int, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1], Default: 0

Returns the current velocity of the motor. This value is different from get-velocity whenever the motor is currently accelerating to a goal set by set-velocity.

tinkerforge call dc-v2-bricklet <uid> set-motion <acceleration> <deceleration>¶

Parameters:	<acceleration> – Type: Int, Unit: 100/32767 %/s, Range: [0 to 216 - 1], Default: 10000 <deceleration> – Type: Int, Unit: 100/32767 %/s, Range: [0 to 216 - 1], Default: 10000
Output:	no output

Sets the acceleration and deceleration of the motor. It is given in velocity/s. An acceleration of 10000 means, that every second the velocity is increased by 10000 (or about 30% duty cycle).

For example: If the current velocity is 0 and you want to accelerate to a velocity of 16000 (about 50% duty cycle) in 10 seconds, you should set an acceleration of 1600.

If acceleration and deceleration is set to 0, there is no speed ramping, i.e. a new velocity is immediately given to the motor.

tinkerforge call dc-v2-bricklet <uid> get-motion¶

Output:	acceleration – Type: Int, Unit: 100/32767 %/s, Range: [0 to 216 - 1], Default: 10000 deceleration – Type: Int, Unit: 100/32767 %/s, Range: [0 to 216 - 1], Default: 10000

Returns the acceleration/deceleration as set by set-motion.

tinkerforge call dc-v2-bricklet <uid> full-brake¶

Output:	no output

Executes an active full brake.

Warning

This function is for emergency purposes, where an immediate brake is necessary. Depending on the current velocity and the strength of the motor, a full brake can be quite violent.

Call set-velocity with 0 if you just want to stop the motor.

tinkerforge call dc-v2-bricklet <uid> get-pwm-frequency¶

Output:	frequency – Type: Int, Unit: 1 Hz, Range: [1 to 20000], Default: 15000

Returns the PWM frequency as set by set-pwm-frequency.

tinkerforge call dc-v2-bricklet <uid> get-power-statistics¶

Output:	voltage – Type: Int, Unit: 1 mV, Range: [0 to 216 - 1] current – Type: Int, Unit: 1 mA, Range: [0 to 216 - 1]

Returns input voltage and current usage of the driver.

Advanced Functions¶

tinkerforge call dc-v2-bricklet <uid> set-drive-mode <mode>¶

Parameters:	<mode> – Type: Int, Range: See symbols, Default: 0
Output:	no output

Sets the drive mode. Possible modes are:

• 0 = Drive/Brake
• 1 = Drive/Coast

These modes are different kinds of motor controls.

In Drive/Brake mode, the motor is always either driving or braking. There is no freewheeling. Advantages are: A more linear correlation between PWM and velocity, more exact accelerations and the possibility to drive with slower velocities.

In Drive/Coast mode, the motor is always either driving or freewheeling. Advantages are: Less current consumption and less demands on the motor and driver chip.

The following symbols are available for this function:

For <mode>:

• drive-mode-drive-brake = 0
• drive-mode-drive-coast = 1

tinkerforge call dc-v2-bricklet <uid> get-drive-mode¶

Output:	mode – Type: Int, Range: See symbols, Default: 0

Returns the drive mode, as set by set-drive-mode.

The following symbols are available for this function:

For mode:

• drive-mode-drive-brake = 0
• drive-mode-drive-coast = 1

tinkerforge call dc-v2-bricklet <uid> set-pwm-frequency <frequency>¶

Parameters:	<frequency> – Type: Int, Unit: 1 Hz, Range: [1 to 20000], Default: 15000
Output:	no output

Sets the frequency of the PWM with which the motor is driven. Often a high frequency is less noisy and the motor runs smoother. However, with a low frequency there are less switches and therefore fewer switching losses. Also with most motors lower frequencies enable higher torque.

If you have no idea what all this means, just ignore this function and use the default frequency, it will very likely work fine.

tinkerforge call dc-v2-bricklet <uid> set-error-led-config <config>¶

Parameters:	<config> – Type: Int, Range: See symbols, Default: 3
Output:	no output

Configures the error LED to be either turned off, turned on, blink in heartbeat mode or show an error.

If the LED is configured to show errors it has three different states:

• Off: No error present.
• 1s interval blinking: Input voltage too low (below 6V).
• 250ms interval blinking: Overtemperature or overcurrent.

The following symbols are available for this function:

For <config>:

• error-led-config-off = 0
• error-led-config-on = 1
• error-led-config-show-heartbeat = 2
• error-led-config-show-error = 3

tinkerforge call dc-v2-bricklet <uid> get-error-led-config¶

Output:	config – Type: Int, Range: See symbols, Default: 3

Returns the LED configuration as set by set-error-led-config

The following symbols are available for this function:

For config:

• error-led-config-off = 0
• error-led-config-on = 1
• error-led-config-show-heartbeat = 2
• error-led-config-show-error = 3

tinkerforge call dc-v2-bricklet <uid> get-spitfp-error-count¶

Output:	error-count-ack-checksum – Type: Int, Range: [0 to 232 - 1] error-count-message-checksum – Type: Int, Range: [0 to 232 - 1] error-count-frame – Type: Int, Range: [0 to 232 - 1] error-count-overflow – Type: Int, Range: [0 to 232 - 1]

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 dc-v2-bricklet <uid> set-status-led-config <config>¶

Parameters:	<config> – Type: Int, Range: See symbols, Default: 3
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:

For <config>:

• status-led-config-off = 0
• status-led-config-on = 1
• status-led-config-show-heartbeat = 2
• status-led-config-show-status = 3

tinkerforge call dc-v2-bricklet <uid> get-status-led-config¶

Output:	config – Type: Int, Range: See symbols, Default: 3

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

The following symbols are available for this function:

For config:

• status-led-config-off = 0
• status-led-config-on = 1
• status-led-config-show-heartbeat = 2
• status-led-config-show-status = 3

tinkerforge call dc-v2-bricklet <uid> get-chip-temperature¶

Output:	temperature – Type: Int, Unit: 1 °C, Range: [-215 to 215 - 1]

Returns the temperature 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 dc-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 dc-v2-bricklet <uid> get-identity¶

Output:

uid – Type: String, Length: up to 8 connected-uid – Type: String, Length: up to 8 position – Type: Char, Range: [a to h, z] hardware-version – Type: Int Array, Length: 3 0: major – Type: Int, Range: [0 to 255] 1: minor – Type: Int, Range: [0 to 255] 2: revision – Type: Int, Range: [0 to 255] firmware-version – Type: Int Array, Length: 3 0: major – Type: Int, Range: [0 to 255] 1: minor – Type: Int, Range: [0 to 255] 2: revision – Type: Int, Range: [0 to 255] device-identifier – Type: Int, Range: [0 to 216 - 1]

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. 

Callback Configuration Functions¶

tinkerforge call dc-v2-bricklet <uid> set-emergency-shutdown-callback-configuration <enabled>¶

Parameters:	<enabled> – Type: Bool, Default: false
Output:	no output

Enable/Disable emergency-shutdown callback.

tinkerforge call dc-v2-bricklet <uid> get-emergency-shutdown-callback-configuration¶

Output:	enabled – Type: Bool, Default: true

Returns the callback configuration as set by set-emergency-shutdown-callback-configuration.

tinkerforge call dc-v2-bricklet <uid> set-velocity-reached-callback-configuration <enabled>¶

Parameters:	<enabled> – Type: Bool, Default: false
Output:	no output

Enable/Disable velocity-reached callback.

tinkerforge call dc-v2-bricklet <uid> get-velocity-reached-callback-configuration¶

Output:	enabled – Type: Bool, Default: false

Returns the callback configuration as set by set-velocity-reached-callback-configuration.

tinkerforge call dc-v2-bricklet <uid> set-current-velocity-callback-configuration <period> <value-has-to-change>¶

Parameters:	<period> – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0 <value-has-to-change> – Type: Bool, Default: false
Output:	no output

The period is the period with which the current-velocity 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.

tinkerforge call dc-v2-bricklet <uid> get-current-velocity-callback-configuration¶

Output:	period – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0 value-has-to-change – Type: Bool, Default: false

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

Callbacks¶

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

tinkerforge dispatch dc-v2-bricklet <uid> example

The available callbacks are described below.

tinkerforge dispatch dc-v2-bricklet <uid> emergency-shutdown¶

Output:	no output

This callback is triggered if either the current consumption is too high (above 5A) or the temperature of the driver chip is too high (above 175°C). These two possibilities are essentially the same, since the temperature will reach this threshold immediately if the motor consumes too much current. In case of a voltage below 3.3V (external or stack) this callback is triggered as well.

If this callback is triggered, the driver chip gets disabled at the same time. That means, set-enabled has to be called to drive the motor again.

Note

This callback only works in Drive/Brake mode (see set-drive-mode). In Drive/Coast mode it is unfortunately impossible to reliably read the overcurrent/overtemperature signal from the driver chip.

tinkerforge dispatch dc-v2-bricklet <uid> velocity-reached¶

Output:	velocity – Type: Int, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1]

This callback is triggered whenever a set velocity is reached. For example: If a velocity of 0 is present, acceleration is set to 5000 and velocity to 10000, the velocity-reached callback will be triggered after about 2 seconds, when the set velocity is actually reached.

Note

Since we can't get any feedback from the DC motor, this only works if the acceleration (see set-motion) is set smaller or equal to the maximum acceleration of the motor. Otherwise the motor will lag behind the control value and the callback will be triggered too early.

tinkerforge dispatch dc-v2-bricklet <uid> current-velocity¶

Output:	velocity – Type: Int, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1]

This callback is triggered with the period that is set by set-current-velocity-callback-configuration. The parameter is the current velocity used by the motor.

The current-velocity callback is only triggered after the set period if there is a change in the velocity.

Internal Functions¶

Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.

tinkerforge call dc-v2-bricklet <uid> set-bootloader-mode <mode>¶

Parameters:	<mode> – Type: Int, Range: See symbols
Output:	status – Type: Int, Range: See 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:

For <mode>:

• bootloader-mode-bootloader = 0
• bootloader-mode-firmware = 1
• bootloader-mode-bootloader-wait-for-reboot = 2
• bootloader-mode-firmware-wait-for-reboot = 3
• bootloader-mode-firmware-wait-for-erase-and-reboot = 4

For status:

• bootloader-status-ok = 0
• bootloader-status-invalid-mode = 1
• bootloader-status-no-change = 2
• bootloader-status-entry-function-not-present = 3
• bootloader-status-device-identifier-incorrect = 4
• bootloader-status-crc-mismatch = 5

tinkerforge call dc-v2-bricklet <uid> get-bootloader-mode¶

Output:	mode – Type: Int, Range: See symbols

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

The following symbols are available for this function:

For mode:

• bootloader-mode-bootloader = 0
• bootloader-mode-firmware = 1
• bootloader-mode-bootloader-wait-for-reboot = 2
• bootloader-mode-firmware-wait-for-reboot = 3
• bootloader-mode-firmware-wait-for-erase-and-reboot = 4

tinkerforge call dc-v2-bricklet <uid> set-write-firmware-pointer <pointer>¶

Parameters:	<pointer> – Type: Int, Unit: 1 B, Range: [0 to 232 - 1]
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 dc-v2-bricklet <uid> write-firmware <data>¶

Parameters:	<data> – Type: Int Array, Length: 64, Range: [0 to 255]
Output:	status – Type: Int, Range: [0 to 255]

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 dc-v2-bricklet <uid> write-uid <uid>¶

Parameters:	<uid> – Type: Int, Range: [0 to 232 - 1]
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 dc-v2-bricklet <uid> read-uid¶

Output:	uid – Type: Int, Range: [0 to 232 - 1]

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