Software / API Bindings / Ruby / API Reference and Examples / Bricks / Silent Stepper Brick

Ruby - Silent Stepper Brick¶

This is the description of the Ruby API bindings for the Silent Stepper Brick. General information and technical specifications for the Silent Stepper Brick are summarized in its hardware description.

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

Examples¶

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

Configuration¶

Download (example_configuration.rb)

#!/usr/bin/env ruby
# -*- ruby encoding: utf-8 -*-

require 'tinkerforge/ip_connection'
require 'tinkerforge/brick_silent_stepper'

include Tinkerforge

HOST = 'localhost'
PORT = 4223
UID = 'XXYYZZ' # Change XXYYZZ to the UID of your Silent Stepper Brick

ipcon = IPConnection.new # Create IP connection
ss = BrickSilentStepper.new UID, ipcon # Create device object

ipcon.connect HOST, PORT # Connect to brickd
# Don't use device before ipcon is connected

ss.set_motor_current 800 # 800mA
ss.set_step_configuration BrickSilentStepper::STEP_RESOLUTION_8, \
                          true # 1/8 steps (interpolated)
ss.set_max_velocity 2000 # Velocity 2000 steps/s

# Slow acceleration (500 steps/s^2),
# Fast deacceleration (5000 steps/s^2)
ss.set_speed_ramping 500, 5000

ss.enable # Enable motor power
ss.set_steps 60000 # Drive 60000 steps forward

puts 'Press key to exit'
$stdin.gets
ss.disable
ipcon.disconnect

Callback¶

Download (example_callback.rb)

#!/usr/bin/env ruby
# -*- ruby encoding: utf-8 -*-

require 'tinkerforge/ip_connection'
require 'tinkerforge/brick_silent_stepper'

include Tinkerforge

HOST = 'localhost'
PORT = 4223
UID = 'XXYYZZ' # Change XXYYZZ to the UID of your Silent Stepper Brick

ipcon = IPConnection.new # Create IP connection
ss = BrickSilentStepper.new UID, ipcon # Create device object

ipcon.connect HOST, PORT # Connect to brickd
# Don't use device before ipcon is connected

# Use position reached callback to program random movement
ss.register_callback(BrickSilentStepper::CALLBACK_POSITION_REACHED) do |position|
  if rand(1) == 0
    steps = 1000 + rand(4000) # steps (forward)
    puts "Driving forward: #{steps} steps"
  else
    steps = rand(4000) - 5000 # steps (backward)
    puts "Driving backward: #{steps} steps"
  end

  vel = 200 + rand(1800) # steps/s
  acc = 100 + rand(900) # steps/s^2
  dec = 100 + rand(900) # steps/s^2
  puts "Configuration (vel, acc, dec): #{vel}, #{acc}, #{dec}"

  ss.set_speed_ramping acc, dec
  ss.set_max_velocity vel
  ss.set_steps steps
end

ss.set_step_configuration BrickSilentStepper::STEP_RESOLUTION_8, \
                          true # 1/8 steps (interpolated)
ss.enable # Enable motor power
ss.set_steps 1 # Drive one step forward to get things going

puts 'Press key to exit'
$stdin.gets
ss.disable
ipcon.disconnect

API¶

All methods listed below are thread-safe.

Basic Functions¶

BrickSilentStepper::new(uid, ipcon) → silent_stepper¶

Parameters:	uid -- str ipcon -- IPConnection

Creates an object with the unique device ID uid:

silent_stepper = BrickSilentStepper.new 'YOUR_DEVICE_UID', ipcon

This object can then be used after the IP Connection is connected (see examples above).

BrickSilentStepper#set_max_velocity(velocity) → nil¶

Parameters:	velocity -- int

Sets the maximum velocity of the stepper motor in steps per second. This function does not start the motor, it merely sets the maximum velocity the stepper motor is accelerated to. To get the motor running use either #set_target_position, #set_steps, #drive_forward or #drive_backward.

BrickSilentStepper#get_max_velocity → int¶: Returns the velocity as set by #set_max_velocity.

BrickSilentStepper#get_current_velocity → int¶: Returns the current velocity of the stepper motor in steps per second.

BrickSilentStepper#set_speed_ramping(acceleration, deacceleration) → nil¶

Parameters:	acceleration -- int deacceleration -- int

Sets the acceleration and deacceleration of the stepper motor. The values are given in steps/s². An acceleration of 1000 means, that every second the velocity is increased by 1000 steps/s.

For example: If the current velocity is 0 and you want to accelerate to a velocity of 8000 steps/s in 10 seconds, you should set an acceleration of 800 steps/s².

An acceleration/deacceleration of 0 means instantaneous acceleration/deacceleration (not recommended)

The default value is 1000 for both

BrickSilentStepper#get_speed_ramping → [int, int]¶

Returns the acceleration and deacceleration as set by #set_speed_ramping.

The returned array has the values acceleration and deacceleration.

BrickSilentStepper#full_brake → nil¶

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 #stop if you just want to stop the motor.

BrickSilentStepper#set_steps(steps) → nil¶

Parameters:	steps -- int

Sets the number of steps the stepper motor should run. Positive values will drive the motor forward and negative values backward. The velocity, acceleration and deacceleration as set by #set_max_velocity and #set_speed_ramping will be used.

BrickSilentStepper#get_steps → int¶: Returns the last steps as set by #set_steps.

BrickSilentStepper#get_remaining_steps → int¶: Returns the remaining steps of the last call of #set_steps. For example, if #set_steps is called with 2000 and #get_remaining_steps is called after the motor has run for 500 steps, it will return 1500.

BrickSilentStepper#drive_forward → nil¶: Drives the stepper motor forward until #drive_backward or #stop is called. The velocity, acceleration and deacceleration as set by #set_max_velocity and #set_speed_ramping will be used.

BrickSilentStepper#drive_backward → nil¶: Drives the stepper motor backward until #drive_forward or #stop is triggered. The velocity, acceleration and deacceleration as set by #set_max_velocity and #set_speed_ramping will be used.

BrickSilentStepper#stop → nil¶: Stops the stepper motor with the deacceleration as set by #set_speed_ramping.

BrickSilentStepper#set_motor_current(current) → nil¶

Parameters:	current -- int

Sets the current in mA with which the motor will be driven. The minimum value is 360mA, the maximum value 1640mA and the default value is 800mA.

Warning

Do not set this value above the specifications of your stepper motor. Otherwise it may damage your motor.

BrickSilentStepper#get_motor_current → int¶: Returns the current as set by #set_motor_current.

BrickSilentStepper#enable → nil¶: Enables the driver chip. The driver parameters can be configured (maximum velocity, acceleration, etc) before it is enabled.

BrickSilentStepper#disable → nil¶: Disables the driver chip. The configurations are kept (maximum velocity, acceleration, etc) but the motor is not driven until it is enabled again.

BrickSilentStepper#is_enabled → bool¶: Returns true if the driver chip is enabled, false otherwise.

BrickSilentStepper#set_basic_configuration(standstill_current, motor_run_current, standstill_delay_time, power_down_time, stealth_threshold, coolstep_threshold, classic_threshold, high_velocity_chopper_mode) → nil¶

Parameters:	standstill_current -- int motor_run_current -- int standstill_delay_time -- int power_down_time -- int stealth_threshold -- int coolstep_threshold -- int classic_threshold -- int high_velocity_chopper_mode -- bool

Sets the basic configuration parameters for the different modes (Stealth, Coolstep, Classic).

Standstill Current: This value can be used to lower the current during stand still. This might be reasonable to reduce the heating of the motor and the Brick. When the motor is in standstill the configured motor phase current will be driven until the configured Power Down Time is elapsed. After that the phase current will be reduced to the standstill current. The elapsed time for this reduction can be configured with the Standstill Delay Time. The unit is in mA and the maximum allowed value is the configured maximum motor current (see #set_motor_current).
Motor Run Current: The value sets the motor current when the motor is running. Use a value of at least one half of the global maximum motor current for a good microstep performance. The unit is in mA and the maximum allowed value is the current motor current. The API maps the entered value to 1/32 ... 32/32 of the maximum motor current. This value should be used to change the motor current during motor movement, whereas the global maximum motor current should not be changed while the motor is moving (see #set_motor_current).
Standstill Delay Time: Controls the duration for motor power down after a motion as soon as standstill is detected and the Power Down Time is expired. A high Standstill Delay Time results in a smooth transition that avoids motor jerk during power down. The value range is 0 to 307ms
Power Down Time: Sets the delay time after a stand still. The value range is 0 to 5222ms.
Stealth Threshold: Sets the upper threshold for Stealth mode in steps/s. The value range is 0-65536 steps/s. If the velocity of the motor goes above this value, Stealth mode is turned off. Otherwise it is turned on. In Stealth mode the torque declines with high speed.
Coolstep Threshold: Sets the lower threshold for Coolstep mode in steps/s. The value range is 0-65536 steps/s. The Coolstep Threshold needs to be above the Stealth Threshold.
Classic Threshold: Sets the lower threshold for classic mode. The value range is 0-65536 steps/s. In classic mode the stepper becomes more noisy, but the torque is maximized.
High Velocity Shopper Mode: If High Velocity Shopper Mode is enabled, the stepper control is optimized to run the stepper motors at high velocities.

If you want to use all three thresholds make sure that Stealth Threshold < Coolstep Threshold < Classic Threshold.

The default values are:

Standstill Current: 200
Motor Run Current: 800
Standstill Delay Time: 0
Power Down Time: 1000
Stealth Threshold: 500
Coolstep Threshold: 500
Classic Threshold: 1000
High Velocity Shopper Mode: false

BrickSilentStepper#get_basic_configuration → [int, int, int, int, int, int, int, bool]¶

Returns the configuration as set by #set_basic_configuration.

The returned array has the values standstill_current, motor_run_current, standstill_delay_time, power_down_time, stealth_threshold, coolstep_threshold, classic_threshold and high_velocity_chopper_mode.

Advanced Functions¶

BrickSilentStepper#set_current_position(position) → nil¶

Parameters:	position -- int

Sets the current steps of the internal step counter. This can be used to set the current position to 0 when some kind of starting position is reached (e.g. when a CNC machine reaches a corner).

BrickSilentStepper#get_current_position → int¶: Returns the current position of the stepper motor in steps. On startup the position is 0. The steps are counted with all possible driving functions (#set_target_position, #set_steps, #drive_forward or #drive_backward). It also is possible to reset the steps to 0 or set them to any other desired value with #set_current_position.

BrickSilentStepper#set_target_position(position) → nil¶

Parameters:	position -- int

Sets the target position of the stepper motor in steps. For example, if the current position of the motor is 500 and #set_target_position is called with 1000, the stepper motor will drive 500 steps forward. It will use the velocity, acceleration and deacceleration as set by #set_max_velocity and #set_speed_ramping.

A call of #set_target_position with the parameter x is equivalent to a call of #set_steps with the parameter (x - #get_current_position).

BrickSilentStepper#get_target_position → int¶: Returns the last target position as set by #set_target_position.

BrickSilentStepper#set_step_configuration(step_resolution, interpolation) → nil¶

Parameters:	step_resolution -- int interpolation -- bool

Sets the step resolution from full-step up to 1/256-step.

If interpolation is turned on, the Silent Stepper Brick will always interpolate your step inputs as 1/256-step. If you use full-step mode with interpolation, each step will generate 256 1/256 steps.

For maximum torque use full-step without interpolation. For maximum resolution use 1/256-step. Turn interpolation on to make the Stepper driving less noisy.

If you often change the speed with high acceleration you should turn the interpolation off.

The default is 1/256-step with interpolation on.

The following constants are available for this function:

BrickSilentStepper::STEP_RESOLUTION_1 = 8
BrickSilentStepper::STEP_RESOLUTION_2 = 7
BrickSilentStepper::STEP_RESOLUTION_4 = 6
BrickSilentStepper::STEP_RESOLUTION_8 = 5
BrickSilentStepper::STEP_RESOLUTION_16 = 4
BrickSilentStepper::STEP_RESOLUTION_32 = 3
BrickSilentStepper::STEP_RESOLUTION_64 = 2
BrickSilentStepper::STEP_RESOLUTION_128 = 1
BrickSilentStepper::STEP_RESOLUTION_256 = 0

BrickSilentStepper#get_step_configuration → [int, bool]¶

Returns the step mode as set by #set_step_configuration.

The following constants are available for this function:

BrickSilentStepper::STEP_RESOLUTION_1 = 8
BrickSilentStepper::STEP_RESOLUTION_2 = 7
BrickSilentStepper::STEP_RESOLUTION_4 = 6
BrickSilentStepper::STEP_RESOLUTION_8 = 5
BrickSilentStepper::STEP_RESOLUTION_16 = 4
BrickSilentStepper::STEP_RESOLUTION_32 = 3
BrickSilentStepper::STEP_RESOLUTION_64 = 2
BrickSilentStepper::STEP_RESOLUTION_128 = 1
BrickSilentStepper::STEP_RESOLUTION_256 = 0

The returned array has the values step_resolution and interpolation.

BrickSilentStepper#get_stack_input_voltage → int¶: Returns the stack input voltage in mV. The stack input voltage is the voltage that is supplied via the stack, i.e. it is given by a Step-Down or Step-Up Power Supply.

BrickSilentStepper#get_external_input_voltage → int¶

Returns the external input voltage in mV. The external input voltage is given via the black power input connector on the Silent Stepper Brick.

If there is an external input voltage and a stack input voltage, the motor will be driven by the external input voltage. If there is only a stack voltage present, the motor will be driven by this voltage.

Warning

This means, if you have a high stack voltage and a low external voltage, the motor will be driven with the low external voltage. If you then remove the external connection, it will immediately be driven by the high stack voltage

BrickSilentStepper#set_spreadcycle_configuration(slow_decay_duration, enable_random_slow_decay, fast_decay_duration, hysteresis_start_value, hysteresis_end_value, sine_wave_offset, chopper_mode, comparator_blank_time, fast_decay_without_comparator) → nil¶

Parameters:	slow_decay_duration -- int enable_random_slow_decay -- bool fast_decay_duration -- int hysteresis_start_value -- int hysteresis_end_value -- int sine_wave_offset -- int chopper_mode -- int comparator_blank_time -- int fast_decay_without_comparator -- bool

Note: If you don't know what any of this means you can very likely keep all of the values as default!

Sets the Spreadcycle configuration parameters. Spreadcycle is a chopper algorithm which actively controls the motor current flow. More information can be found in the TMC2130 datasheet on page 47 (7 spreadCycle and Classic Chopper).

Slow Decay Duration: Controls duration of off time setting of slow decay phase. The value range is 0-15. 0 = driver disabled, all bridges off. Use 1 only with Comparator Blank time >= 2.
Enable Random Slow Decay: Set to false to fix chopper off time as set by Slow Decay Duration. If you set it to true, Decay Duration is randomly modulated.
Fast Decay Duration: Sets the fast decay duration. The value range is 0-15. This parameters is only used if the Chopper Mode is set to Fast Decay.
Hysteresis Start Value: Sets the hysteresis start value. The value range is 0-7. This parameter is only used if the Chopper Mode is set to Spread Cycle.
Hysteresis End Value: Sets the hysteresis end value. The value range is -3 to 12. This parameter is only used if the Chopper Mode is set to Spread Cycle.
Sine Wave Offset: Sets the sine wave offset. The value range is -3 to 12. This parameters is only used if the Chopper Mode is set to Fast Decay. 1/512 of the value becomes added to the absolute value of the sine wave.
Chopper Mode: 0 = Spread Cycle, 1 = Fast Decay.
Comparator Blank Time: Sets the blank time of the comparator. Available values are
- 0 = 16 clocks,
- 1 = 24 clocks,
- 2 = 36 clocks and
- 3 = 54 clocks.
A value of 1 or 2 is recommended for most applications.
Fast Decay Without Comparator: If set to true the current comparator usage for termination of the fast decay cycle is disabled.

The default values are:

Slow Decay Duration: 4
Enable Random Slow Decay: 0
Fast Decay Duration: 0
Hysteresis Start Value: 0
Hysteresis End Value: 0
Sine Wave Offset: 0
Chopper Mode: 0
Comparator Blank Time: 1
Fast Decay Without Comparator: false

The following constants are available for this function:

BrickSilentStepper::CHOPPER_MODE_SPREAD_CYCLE = 0
BrickSilentStepper::CHOPPER_MODE_FAST_DECAY = 1

BrickSilentStepper#get_spreadcycle_configuration → [int, bool, int, int, int, int, int, int, bool]¶

Returns the configuration as set by #set_basic_configuration.

The following constants are available for this function:

BrickSilentStepper::CHOPPER_MODE_SPREAD_CYCLE = 0
BrickSilentStepper::CHOPPER_MODE_FAST_DECAY = 1

The returned array has the values slow_decay_duration, enable_random_slow_decay, fast_decay_duration, hysteresis_start_value, hysteresis_end_value, sine_wave_offset, chopper_mode, comparator_blank_time and fast_decay_without_comparator.

BrickSilentStepper#set_stealth_configuration(enable_stealth, amplitude, gradient, enable_autoscale, force_symmetric, freewheel_mode) → nil¶

Parameters:	enable_stealth -- bool amplitude -- int gradient -- int enable_autoscale -- bool force_symmetric -- bool freewheel_mode -- int

Note: If you don't know what any of this means you can very likely keep all of the values as default!

Sets the configuration relevant for Stealth mode.

Enable Stealth: If set to true the stealth mode is enabled, if set to false the stealth mode is disabled, even if the speed is below the threshold set in #set_basic_configuration.
Amplitude: If autoscale is disabled, the PWM amplitude is scaled by this value. If autoscale is enabled, this value defines the maximum PWM amplitude change per half wave. The value range is 0-255.
Gradient: If autoscale is disabled, the PWM gradient is scaled by this value. If autoscale is enabled, this value defines the maximum PWM gradient. With autoscale a value above 64 is recommended, otherwise the regulation might not be able to measure the current. The value range is 0-255.
Enable Autoscale: If set to true, automatic current control is used. Otherwise the user defined amplitude and gradient are used.
Force Symmetric: If true, A symmetric PWM cycle is enforced. Otherwise the PWM value may change within each PWM cycle.
Freewheel Mode: The freewheel mode defines the behavior in stand still if the Standstill Current (see #set_basic_configuration) is set to 0.

The default values are:

Enable Stealth: true
Amplitude: 128
Gradient: 4
Enable Autoscale: true
Force Symmetric: false
Freewheel Mode: 0 (Normal)

The following constants are available for this function:

BrickSilentStepper::FREEWHEEL_MODE_NORMAL = 0
BrickSilentStepper::FREEWHEEL_MODE_FREEWHEELING = 1
BrickSilentStepper::FREEWHEEL_MODE_COIL_SHORT_LS = 2
BrickSilentStepper::FREEWHEEL_MODE_COIL_SHORT_HS = 3

BrickSilentStepper#get_stealth_configuration → [bool, int, int, bool, bool, int]¶

Returns the configuration as set by #set_stealth_configuration.

The following constants are available for this function:

BrickSilentStepper::FREEWHEEL_MODE_NORMAL = 0
BrickSilentStepper::FREEWHEEL_MODE_FREEWHEELING = 1
BrickSilentStepper::FREEWHEEL_MODE_COIL_SHORT_LS = 2
BrickSilentStepper::FREEWHEEL_MODE_COIL_SHORT_HS = 3

The returned array has the values enable_stealth, amplitude, gradient, enable_autoscale, force_symmetric and freewheel_mode.

BrickSilentStepper#set_coolstep_configuration(minimum_stallguard_value, maximum_stallguard_value, current_up_step_width, current_down_step_width, minimum_current, stallguard_threshold_value, stallguard_mode) → nil¶

Parameters:	minimum_stallguard_value -- int maximum_stallguard_value -- int current_up_step_width -- int current_down_step_width -- int minimum_current -- int stallguard_threshold_value -- int stallguard_mode -- int

Note: If you don't know what any of this means you can very likely keep all of the values as default!

Sets the configuration relevant for Coolstep.

Minimum Stallguard Value: If the Stallguard result falls below this value*32, the motor current is increased to reduce motor load angle. The value range is 0-15. A value of 0 turns Coolstep off.
Maximum Stallguard Value: If the Stallguard result goes above (Min Stallguard Value + Max Stallguard Value + 1) * 32, the motor current is decreased to save energy.
Current Up Step Width: Sets the up step increment per Stallguard value. The value range is 0-3, corresponding to the increments 1, 2, 4 and 8.
Current Down Step Width: Sets the down step decrement per Stallguard value. The value range is 0-3, corresponding to the decrements 1, 2, 8 and 16.
Minimum Current: Sets the minimum current for Coolstep current control. You can choose between half and quarter of the run current.
Stallguard Threshold Value: Sets the level for stall output (see #get_driver_status). The value range is -64 to +63. A lower value gives a higher sensitivity. You have to find a suitable value for your motor by trial and error, 0 works for most motors.
Stallguard Mode: Set to 0 for standard resolution or 1 for filtered mode. In filtered mode the Stallguard signal will be updated every four full-steps.

The default values are:

Minimum Stallguard Value: 2
Maximum Stallguard Value: 10
Current Up Step Width: 0
Current Down Step Width: 0
Minimum Current: 0
Stallguard Threshold Value: 0
Stallguard Mode: 0

The following constants are available for this function:

BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_1 = 0
BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_2 = 1
BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_4 = 2
BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_8 = 3
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_1 = 0
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_2 = 1
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_8 = 2
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_32 = 3
BrickSilentStepper::MINIMUM_CURRENT_HALF = 0
BrickSilentStepper::MINIMUM_CURRENT_QUARTER = 1
BrickSilentStepper::STALLGUARD_MODE_STANDARD = 0
BrickSilentStepper::STALLGUARD_MODE_FILTERED = 1

BrickSilentStepper#get_coolstep_configuration → [int, int, int, int, int, int, int]¶

Returns the configuration as set by #set_coolstep_configuration.

The following constants are available for this function:

BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_1 = 0
BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_2 = 1
BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_4 = 2
BrickSilentStepper::CURRENT_UP_STEP_INCREMENT_8 = 3
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_1 = 0
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_2 = 1
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_8 = 2
BrickSilentStepper::CURRENT_DOWN_STEP_DECREMENT_32 = 3
BrickSilentStepper::MINIMUM_CURRENT_HALF = 0
BrickSilentStepper::MINIMUM_CURRENT_QUARTER = 1
BrickSilentStepper::STALLGUARD_MODE_STANDARD = 0
BrickSilentStepper::STALLGUARD_MODE_FILTERED = 1

The returned array has the values minimum_stallguard_value, maximum_stallguard_value, current_up_step_width, current_down_step_width, minimum_current, stallguard_threshold_value and stallguard_mode.

BrickSilentStepper#set_misc_configuration(disable_short_to_ground_protection, synchronize_phase_frequency) → nil¶

Parameters:	disable_short_to_ground_protection -- bool synchronize_phase_frequency -- int

Note: If you don't know what any of this means you can very likely keep all of the values as default!

Sets miscellaneous configuration parameters.

Disable Short To Ground Protection: Set to false to enable short to ground protection, otherwise it is disabled.
Synchronize Phase Frequency: With this parameter you can synchronize the chopper for both phases of a two phase motor to avoid the occurrence of a beat. The value range is 0-15. If set to 0, the synchronization is turned off. Otherwise the synchronization is done through the formula f_sync = f_clk/(value*64). In Classic Mode the synchronization is automatically switched off. f_clk is 12.8MHz.

The default values are:

Disable Short To Ground Protection: 0
Synchronize Phase Frequency: 0

BrickSilentStepper#get_misc_configuration → [bool, int]¶

Returns the configuration as set by #set_misc_configuration.

The returned array has the values disable_short_to_ground_protection and synchronize_phase_frequency.

BrickSilentStepper#get_driver_status → [int, int, int, bool, int, bool, int, int]¶

Returns the current driver status.

Open Load: Indicates if an open load is present on phase A, B or both. This could mean that there is a problem with the wiring of the motor. False detection can occur in fast motion as well as during stand still.
Short To Ground: Indicates if a short to ground is present on phase A, B or both. If this is detected the driver automatically becomes disabled and stays disabled until it is enabled again manually.
Over Temperature: The over temperature indicator switches to "Warning" if the driver IC warms up. The warning flag is expected during long duration stepper uses. If the temperature limit is reached the indicator switches to "Limit". In this case the driver becomes disabled until it cools down again.
Motor Stalled: Is true if a motor stall was detected.
Actual Motor Current: Indicates the actual current control scaling as used in Coolstep mode. The returned value is between 0 and 31. It represents a multiplier of 1/32 to 32/32 of the Motor Run Current as set by #set_basic_configuration. Example: If a Motor Run Current of 1000mA was set and the returned value is 15, the Actual Motor Current is 16/32*1000mA = 500mA.
Stallguard Result: Indicates the load of the motor. A lower value signals a higher load. Per trial and error you can find out which value corresponds to a suitable torque for the velocity used in your application. After that you can use this threshold value to find out if a motor stall becomes probable and react on it (e.g. decrease velocity). During stand still this value can not be used for stall detection, it shows the chopper on-time for motor coil A.
Stealth Voltage Amplitude: Shows the actual PWM scaling. In Stealth mode it can be used to detect motor load and stall if autoscale is enabled (see #set_stealth_configuration).

The following constants are available for this function:

BrickSilentStepper::OPEN_LOAD_NONE = 0
BrickSilentStepper::OPEN_LOAD_PHASE_A = 1
BrickSilentStepper::OPEN_LOAD_PHASE_B = 2
BrickSilentStepper::OPEN_LOAD_PHASE_AB = 3
BrickSilentStepper::SHORT_TO_GROUND_NONE = 0
BrickSilentStepper::SHORT_TO_GROUND_PHASE_A = 1
BrickSilentStepper::SHORT_TO_GROUND_PHASE_B = 2
BrickSilentStepper::SHORT_TO_GROUND_PHASE_AB = 3
BrickSilentStepper::OVER_TEMPERATURE_NONE = 0
BrickSilentStepper::OVER_TEMPERATURE_WARNING = 1
BrickSilentStepper::OVER_TEMPERATURE_LIMIT = 2

The returned array has the values open_load, short_to_ground, over_temperature, motor_stalled, actual_motor_current, full_step_active, stallguard_result and stealth_voltage_amplitude.

BrickSilentStepper#set_time_base(time_base) → nil¶

Parameters:	time_base -- int

Sets the time base of the velocity and the acceleration of the Silent Stepper Brick (in seconds).

For example, if you want to make one step every 1.5 seconds, you can set the time base to 15 and the velocity to 10. Now the velocity is 10steps/15s = 1steps/1.5s.

The default value is 1.

BrickSilentStepper#get_time_base → int¶: Returns the time base as set by #set_time_base.

BrickSilentStepper#get_all_data → [int, int, int, int, int, int]¶

Returns the following parameters: The current velocity, the current position, the remaining steps, the stack voltage, the external voltage and the current consumption of the stepper motor.

The current consumption is calculated by multiplying the Actual Motor Current value (see #set_basic_configuration) with the Motor Run Current (see #get_driver_status). This is an internal calculation of the driver, not an independent external measurement.

The current consumption calculation was broken up to firmware 2.0.1, it is fixed since firmware 2.0.2.

There is also a callback for this function, see ::CALLBACK_ALL_DATA callback.

The returned array has the values current_velocity, current_position, remaining_steps, stack_voltage, external_voltage and current_consumption.

BrickSilentStepper#get_api_version → [int, int, int]¶: Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

BrickSilentStepper#get_response_expected(function_id) → bool¶

Parameters:	function_id -- int

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by #set_response_expected. For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

See #set_response_expected for the list of function ID constants available for this function.

BrickSilentStepper#set_response_expected(function_id, response_expected) → nil¶

Parameters:	function_id -- int response_expected -- bool

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

The following function ID constants are available for this function:

BrickSilentStepper::FUNCTION_SET_MAX_VELOCITY = 1
BrickSilentStepper::FUNCTION_SET_SPEED_RAMPING = 4
BrickSilentStepper::FUNCTION_FULL_BRAKE = 6
BrickSilentStepper::FUNCTION_SET_CURRENT_POSITION = 7
BrickSilentStepper::FUNCTION_SET_TARGET_POSITION = 9
BrickSilentStepper::FUNCTION_SET_STEPS = 11
BrickSilentStepper::FUNCTION_SET_STEP_CONFIGURATION = 14
BrickSilentStepper::FUNCTION_DRIVE_FORWARD = 16
BrickSilentStepper::FUNCTION_DRIVE_BACKWARD = 17
BrickSilentStepper::FUNCTION_STOP = 18
BrickSilentStepper::FUNCTION_SET_MOTOR_CURRENT = 22
BrickSilentStepper::FUNCTION_ENABLE = 24
BrickSilentStepper::FUNCTION_DISABLE = 25
BrickSilentStepper::FUNCTION_SET_BASIC_CONFIGURATION = 27
BrickSilentStepper::FUNCTION_SET_SPREADCYCLE_CONFIGURATION = 29
BrickSilentStepper::FUNCTION_SET_STEALTH_CONFIGURATION = 31
BrickSilentStepper::FUNCTION_SET_COOLSTEP_CONFIGURATION = 33
BrickSilentStepper::FUNCTION_SET_MISC_CONFIGURATION = 35
BrickSilentStepper::FUNCTION_SET_MINIMUM_VOLTAGE = 38
BrickSilentStepper::FUNCTION_SET_TIME_BASE = 42
BrickSilentStepper::FUNCTION_SET_ALL_DATA_PERIOD = 45
BrickSilentStepper::FUNCTION_SET_SPITFP_BAUDRATE_CONFIG = 231
BrickSilentStepper::FUNCTION_SET_SPITFP_BAUDRATE = 234
BrickSilentStepper::FUNCTION_ENABLE_STATUS_LED = 238
BrickSilentStepper::FUNCTION_DISABLE_STATUS_LED = 239
BrickSilentStepper::FUNCTION_RESET = 243

BrickSilentStepper#set_response_expected_all(response_expected) → nil¶

Parameters:	response_expected -- bool

Changes the response expected flag for all setter and callback configuration functions of this device at once.

BrickSilentStepper#set_spitfp_baudrate_config(enable_dynamic_baudrate, minimum_dynamic_baudrate) → nil¶

Parameters:	enable_dynamic_baudrate -- bool minimum_dynamic_baudrate -- int

The SPITF protocol can be used with a dynamic baudrate. If the dynamic baudrate is enabled, the Brick will try to adapt the baudrate for the communication between Bricks and Bricklets according to the amount of data that is transferred.

The baudrate will be increased exponentially if lots of data is send/received and decreased linearly if little data is send/received.

This lowers the baudrate in applications where little data is transferred (e.g. a weather station) and increases the robustness. If there is lots of data to transfer (e.g. Thermal Imaging Bricklet) it automatically increases the baudrate as needed.

In cases where some data has to transferred as fast as possible every few seconds (e.g. RS485 Bricklet with a high baudrate but small payload) you may want to turn the dynamic baudrate off to get the highest possible performance.

The maximum value of the baudrate can be set per port with the function #set_spitfp_baudrate. If the dynamic baudrate is disabled, the baudrate as set by #set_spitfp_baudrate will be used statically.

The minimum dynamic baudrate has a value range of 400000 to 2000000 baud.

By default dynamic baudrate is enabled and the minimum dynamic baudrate is 400000.

New in version 2.0.4 (Firmware).

BrickSilentStepper#get_spitfp_baudrate_config → [bool, int]¶

Returns the baudrate config, see #set_spitfp_baudrate_config.

New in version 2.0.4 (Firmware).

The returned array has the values enable_dynamic_baudrate and minimum_dynamic_baudrate.

BrickSilentStepper#get_send_timeout_count(communication_method) → int¶

Parameters:	communication_method -- int

Returns the timeout count for the different communication methods.

The methods 0-2 are available for all Bricks, 3-7 only for Master Bricks.

This function is mostly used for debugging during development, in normal operation the counters should nearly always stay at 0.

The following constants are available for this function:

BrickSilentStepper::COMMUNICATION_METHOD_NONE = 0
BrickSilentStepper::COMMUNICATION_METHOD_USB = 1
BrickSilentStepper::COMMUNICATION_METHOD_SPI_STACK = 2
BrickSilentStepper::COMMUNICATION_METHOD_CHIBI = 3
BrickSilentStepper::COMMUNICATION_METHOD_RS485 = 4
BrickSilentStepper::COMMUNICATION_METHOD_WIFI = 5
BrickSilentStepper::COMMUNICATION_METHOD_ETHERNET = 6
BrickSilentStepper::COMMUNICATION_METHOD_WIFI_V2 = 7

BrickSilentStepper#set_spitfp_baudrate(bricklet_port, baudrate) → nil¶

Parameters:	bricklet_port -- str baudrate -- int

Sets the baudrate for a specific Bricklet port ('a' - 'd'). The baudrate can be in the range 400000 to 2000000.

If you want to increase the throughput of Bricklets you can increase the baudrate. If you get a high error count because of high interference (see #get_spitfp_error_count) you can decrease the baudrate.

If the dynamic baudrate feature is enabled, the baudrate set by this function corresponds to the maximum baudrate (see #set_spitfp_baudrate_config).

Regulatory testing is done with the default baudrate. If CE compatibility or similar is necessary in you applications we recommend to not change the baudrate.

The default baudrate for all ports is 1400000.

BrickSilentStepper#get_spitfp_baudrate(bricklet_port) → int¶

Parameters:	bricklet_port -- str

Returns the baudrate for a given Bricklet port, see #set_spitfp_baudrate.

BrickSilentStepper#get_spitfp_error_count(bricklet_port) → [int, int, int, int]¶

Parameters:	bricklet_port -- str

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 Brick side. All Bricklets have a similar function that returns the errors on the Bricklet side.

The returned array has the values error_count_ack_checksum, error_count_message_checksum, error_count_frame and error_count_overflow.

BrickSilentStepper#enable_status_led → nil¶

Enables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

BrickSilentStepper#disable_status_led → nil¶

Disables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

BrickSilentStepper#is_status_led_enabled → bool¶: Returns true if the status LED is enabled, false otherwise.

BrickSilentStepper#get_protocol1_bricklet_name(port) → [int, [int, int, int], str]¶

Parameters:	port -- str

Returns the firmware and protocol version and the name of the Bricklet for a given port.

This functions sole purpose is to allow automatic flashing of v1.x.y Bricklet plugins.

The returned array has the values protocol_version, firmware_version and name.

BrickSilentStepper#get_chip_temperature → int¶

Returns the temperature in °C/10 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 an accuracy of +-15%. Practically it is only useful as an indicator for temperature changes.

BrickSilentStepper#reset → nil¶

Calling this function will reset the Brick. Calling this function on a Brick inside of a stack will reset the whole stack.

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

BrickSilentStepper#get_identity → [str, str, str, [int, int, int], [int, int, int], int]¶

Returns the UID, the UID where the Brick is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be '0'-'8' (stack position).

The device identifier numbers can be found here. There is also a constant for the device identifier of this Brick.

The returned array has the values uid, connected_uid, position, hardware_version, firmware_version and device_identifier.

Callback Configuration Functions¶

BrickSilentStepper#register_callback(callback_id) { |param [, ...]| block } → nil¶

Parameters:	callback_id -- int

Registers the given block with the given callback_id.

The available callback IDs with corresponding function signatures are listed below.

BrickSilentStepper#set_minimum_voltage(voltage) → nil¶

Parameters:	voltage -- int

Sets the minimum voltage in mV, below which the ::CALLBACK_UNDER_VOLTAGE callback is triggered. The minimum possible value that works with the Silent Stepper Brick is 8V. You can use this function to detect the discharge of a battery that is used to drive the stepper motor. If you have a fixed power supply, you likely do not need this functionality.

The default value is 8V.

BrickSilentStepper#get_minimum_voltage → int¶: Returns the minimum voltage as set by #set_minimum_voltage.

BrickSilentStepper#set_all_data_period(period) → nil¶

Parameters:	period -- int

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

BrickSilentStepper#get_all_data_period → int¶: Returns the period as set by #set_all_data_period.

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the #register_callback function of the device object. The first parameter is the callback ID and the second parameter is a block:

silent_stepper.register_callback BrickSilentStepper::CALLBACK_EXAMPLE, do |param|
  puts "#{param}"
end

The available constants with inherent number and type of parameters 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.

BrickSilentStepper::CALLBACK_UNDER_VOLTAGE¶

Parameters:	voltage -- int

This callback is triggered when the input voltage drops below the value set by #set_minimum_voltage. The parameter is the current voltage given in mV.

BrickSilentStepper::CALLBACK_POSITION_REACHED¶

Parameters:	position -- int

This callback is triggered when a position set by #set_steps or #set_target_position is reached.

Note

Since we can't get any feedback from the stepper motor, this only works if the acceleration (see #set_speed_ramping) 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.

BrickSilentStepper::CALLBACK_ALL_DATA¶

Parameters:	current_velocity -- int current_position -- int remaining_steps -- int stack_voltage -- int external_voltage -- int current_consumption -- int

This callback is triggered periodically with the period that is set by #set_all_data_period. The parameters are: the current velocity, the current position, the remaining steps, the stack voltage, the external voltage and the current consumption of the stepper motor.

BrickSilentStepper::CALLBACK_NEW_STATE¶

Parameters:	state_new -- int state_previous -- int

This callback is triggered whenever the Silent Stepper Brick enters a new state. It returns the new state as well as the previous state.

The following constants are available for this function:

BrickSilentStepper::STATE_STOP = 1
BrickSilentStepper::STATE_ACCELERATION = 2
BrickSilentStepper::STATE_RUN = 3
BrickSilentStepper::STATE_DEACCELERATION = 4
BrickSilentStepper::STATE_DIRECTION_CHANGE_TO_FORWARD = 5
BrickSilentStepper::STATE_DIRECTION_CHANGE_TO_BACKWARD = 6

Constants¶

BrickSilentStepper::DEVICE_IDENTIFIER¶

This constant is used to identify a Silent Stepper Brick.

The #get_identity() function and the ::CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

BrickSilentStepper::DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a Silent Stepper Brick.