Python API

This section documents the Python interface to the BenHW SDK.

The Python API provides a Pythonic wrapper around the C API, with automatic memory management, exception handling, and simplified function signatures.

The Python SDK is available on PyPI and can be installed using pip:

pip install benhw

The benhw PyPI package comes bundled with the BenHW DLL, so no separate DLL installation is required. The package automatically manages the DLL loading and initialization.

The main interface to the BenHW SDK is through the BenHW class, which provides methods corresponding to each C API function.

from benhw import BenHW, tokens, SdkException

hw = BenHW() # automatically picks up bundled BenHW dll
try:
 dll_version:str = hw.version()
 hw.build_system_model("absolute/path/to/system.cfg")
 hw.load_setup("absolute/path/to/system.atr")
 hw.initialise()
 hw.park()
 hw.zero_calibration(200.0,400.0)
 hw.select_wavelength(300.0)
 reading:float = hw.automeasure()
 print(reading)
except SdkException as e:
 print(e)

BenHW.close

DLL versions 4.4.13 and above

Close and clean up the system model.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.close()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Frees the system model and releases all resources. Call this before exiting your application. This function instructs the DLL to destroy the system model and prepare for unloading.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.automeasure

DLL versions 4.4.13 and above

Perform an automatic measurement with autoranging.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    reading = hw.automeasure()
    print(f"reading: {reading}")
except SdkException as e:
    print(f"Error: {e}")

Description

Takes a measurement with automatic gain ranging. The detector will automatically adjust its range to get the best reading. Takes the Analogue-digital Converter (ADC) offset and dark current (previously obtained by zero_calibration) into account. Negative values are clamped to zero unless AllowNegative is set.

Returns

reading (````): Measurement reading value or array

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • AdcOverloadException: Analogue-digital Converter (ADC) overload detected - the input signal is too strong for the current range setting.

  • AdcReadErrorException: Analogue-digital Converter (ADC) is not responding or failed to complete a read operation.

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.autorange

DLL versions 4.4.13 and above

Automatically adjust the detector range.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.autorange()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Adjusts the amplifier gain range to optimize the signal for measurement. Should be called before taking measurements if the signal level has changed significantly. This auto-ranges the amplifier(s) in the active group.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.build_group

DLL versions 4.4.13 and above

Create a new component group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    group_number = hw.build_group()
    print(f"group_number: {group_number}")
except SdkException as e:
    print(f"Error: {e}")

Description

Creates a new, empty group for organizing components. Groups allow multiple components to be controlled together. The DLL allows up to 10 component groups. Returns the group number if successful.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.build_system_model

DLL versions 4.4.13 and above

Load and compile a system configuration file.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    config_file = "system.cfg"

    error = hw.build_system_model(config_file)
    print(f"error: {error}")
except SdkException as e:
    print(f"Error: {e}")

Description

Parses the configuration file and builds the system model representing your hardware setup. This must be called before any other operations. If an error occurs, the error message is written to the error buffer. This function must succeed before any other DLL function is called.

Parameters

  • config_file (str) - Path to the system configuration file

Returns

error (````): Error message

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.close_shutter

DLL versions 4.4.13 and above

Close the monochromator shutter.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.close_shutter()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Closes the shutter on the current monochromator to block light. Useful for taking dark measurements. This function sends the filter wheel in the monochromator of the active group to its shutter position.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.component_select_wl

DLL versions 4.4.13 and above

Set the wavelength for a specific component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    wl = 550.0

    settle = hw.component_select_wl(id, wl)
    print(f"settle: {settle}")
except SdkException as e:
    print(f"Error: {e}")

Description

Sets the wavelength for a named monochromator component. Returns the settle delay time needed before taking measurements. This function sends the specified component to the specified wavelength and recommends a settle delay time before any readings are taken. It does not perform the delay itself.

Parameters

  • id (str) - Component identifier string

  • wl (float) - Wavelength value in nanometers

Returns

settle (````): Settle delay time in milliseconds after wavelength change

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.


BenHW.camera_measurement

DLL versions 4.4.13 and above

Take a measurement from a camera/array detector.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    number = 100

    result = hw.camera_measurement(id, number)
    print(f"wls: {result.wls}")
    print(f"readings: {result.readings}")
except SdkException as e:
    print(f"Error: {e}")

Description

Captures spectral data from a camera or diode array detector. Returns wavelengths and intensity readings for each pixel. This function instructs the DLL to take a camera measurement using the camera defined by the id string. The camera measurement itself is performed by the external DLL defined in the system configuration file for the relevant camera.

Parameters

  • id (str) - Component identifier string

  • number (int) - Number of data points or pixels

Returns

A BI_camera_measurement_result object containing:

  • wls (````): Array of wavelength values in nanometers

  • readings (````): Array of measurement readings

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.camera_get_wls

DLL versions 4.4.13 and above

Get wavelength calibration for camera pixels.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"

    wls = hw.camera_get_wls(id)
    print(f"wls: {wls}")
except SdkException as e:
    print(f"Error: {e}")

Description

Retrieves the wavelength corresponding to each pixel of the camera or array detector.

Parameters

  • id (str) - Component identifier string

Returns

wls (````): Array of wavelength values in nanometers

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.camera_zero_calibration

DLL versions 4.4.13 and above

Perform zero calibration for camera detector (obsolete).

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    start_wl = 400.0
    stop_wl = 800.0

    hw.camera_zero_calibration(id, start_wl, stop_wl)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Legacy function for camera zero calibration. This function is obsolete and does nothing. Kept for backwards compatibility with BenWin+.

Parameters

  • id (str) - Component identifier string

  • start_wl (float) - Starting wavelength for the range in nanometers

  • stop_wl (float) - Ending wavelength for the range in nanometers

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.camera_get_zero_calibration_info

DLL versions 4.4.13 and above

Get zero calibration data for camera (obsolete).

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"

    result = hw.camera_get_zero_calibration_info(id)
    print(f"wavelength: {result.wavelength}")
    print(f"DarkCurrent: {result.DarkCurrent}")
except SdkException as e:
    print(f"Error: {e}")

Description

Legacy function for retrieving camera zero calibration data. This function is obsolete and does nothing. Kept for backwards compatibility with BenWin+.

Parameters

  • id (str) - Component identifier string

Returns

A BI_camera_get_zero_calibration_info_result object containing:

  • wavelength (````): Wavelength value in nanometers

  • DarkCurrent (````): Array of dark current calibration values

  • ADCOffset (````): Array of ADC offset calibration values

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.delete_group

DLL versions 4.4.13 and above

Delete a component group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    n = 1

    remaining_groups = hw.delete_group(n)
    print(f"remaining_groups: {remaining_groups}")
except SdkException as e:
    print(f"Error: {e}")

Description

Removes a previously created group. Returns the number of remaining groups.

Parameters

  • n (int) - Group number or count value

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.display_setup_window

DLL versions 4.4.13 and above

Show the setup window for a component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    hinstance = 0

    hw.display_setup_window(id, hinstance)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Displays the configuration dialog for a hardware component if one is available. Requires a window handle from the calling application.

Parameters

  • id (str) - Component identifier string

  • hinstance (int) - Window handle for displaying dialog

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.

  • NoSetupWindowException: No setup window is available for the specified component.


BenHW.display_advanced_window

DLL versions 4.4.13 and above

Show the advanced setup window for a component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    hinstance = 0

    hw.display_advanced_window(id, hinstance)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Displays the advanced configuration dialog for a hardware component if one is available. Requires a window handle from the calling application.

Parameters

  • id (str) - Component identifier string

  • hinstance (int) - Window handle for displaying dialog

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.

  • NoSetupWindowException: No setup window is available for the specified component.


BenHW.get

DLL versions 4.4.13 and above

Get a numeric attribute value from a component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    token = 10
    index = 0

    value = hw.get(id, token, index)
    print(f"value: {value}")
except SdkException as e:
    print(f"Error: {e}")

Description

Retrieves a numeric (double) attribute from a hardware component. Use tokens to specify which attribute to read. The index parameter is used for multi-value attributes (usually 0).

Parameters

  • id (str) - Component identifier string

  • token (int) - Token identifier for the attribute to access

  • index (int) - Index for multi-value attributes (usually 0 for single values)

Returns

value (````): Numeric value to set or retrieve

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.

  • InvalidAttributeException: The function was passed an attribute token referring to an attribute that does not exist or is inaccessible for the specified component.

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.

  • InvalidTokenException: The function was passed an invalid attribute token that is not recognized.


BenHW.get_str

DLL versions 4.4.13 and above

Get a string attribute value from a component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    token = 10
    index = 0

    s = hw.get_str(id, token, index)
    print(f"s: {s}")
except SdkException as e:
    print(f"Error: {e}")

Description

Retrieves a string attribute from a hardware component. Use tokens to specify which attribute to read. Buffer must be pre-allocated (256 bytes recommended).

Parameters

  • id (str) - Component identifier string

  • token (int) - Token identifier for the attribute to access

  • index (int) - Index for multi-value attributes (usually 0 for single values)

Returns

s (````): String value or buffer for text data

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.

  • InvalidAttributeException: The function was passed an attribute token referring to an attribute that does not exist or is inaccessible for the specified component.

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.

  • InvalidTokenException: The function was passed an invalid attribute token that is not recognized.


BenHW.get_c_group

DLL versions 4.4.13 and above

Get the current active group number.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    n = hw.get_c_group()
    print(f"n: {n}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the number of the currently active component group.

Returns

n (````): Group number or count value

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_component_list

DLL versions 4.4.13 and above

Get a comma-separated list of all components.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    list = hw.get_component_list()
    print(f"list: {list}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns a string containing the IDs of all components in the system, separated by commas.

Returns

list (````): Comma-separated list of component IDs

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_group

DLL versions 4.4.13 and above

Get the component IDs in a specific group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    n = 1

    s = hw.get_group(n)
    print(f"s: {s}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns a comma-separated string of component IDs that belong to the specified group.

Parameters

  • n (int) - Group number or count value

Returns

s (````): Comma-separated list of component IDs

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_hardware_type

DLL versions 4.4.13 and above

Get the hardware type constant for a component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"

    hardwareType = hw.get_hardware_type(id)
    print(f"hardwareType: {hardwareType}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the hardware type identifier (e.g., BenMono, BenADC) for a component. Use this to determine what kind of hardware a component represents. See Hardware Types in Tokens list.

Parameters

  • id (str) - Component identifier string

Returns

hardwareType (````): Hardware type identifier token constant

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.


BenHW.get_log

DLL versions 4.4.13 and above

Retrieve accumulated log messages.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    log = hw.get_log()
    print(f"log: {log}")
except SdkException as e:
    print(f"Error: {e}")

Description

Gets the log messages that have been accumulated during operation.

Returns

log (````): Bytes containing log content. May contain r characters.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_log_size

DLL versions 4.4.13 and above

Get the size of accumulated log messages.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    size = hw.get_log_size()
    print(f"size: {size}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the number of bytes needed to store the accumulated log messages. Call this before get_log to allocate appropriate buffer size.

Returns

size (````): Number of bytes

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_mono_items

DLL versions 4.4.13 and above

List components associated with a monochromator.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    monoID = "mono1"

    ItemIDs = hw.get_mono_items(monoID)
    print(f"ItemIDs: {ItemIDs}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns a comma-separated list of component IDs that are part of a monochromator (gratings, filters, etc.). Buffer must be pre-allocated.

Parameters

  • monoID (str) - Monochromator component identifier

Returns

ItemIDs (````): Comma-separated list of item IDs

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_min_step

DLL versions 4.4.13 and above

Get the minimum wavelength step for a wavelength range.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    group = 1
    start_wl = 400.0
    stop_wl = 800.0

    min_step = hw.get_min_step(group, start_wl, stop_wl)
    print(f"min_step: {min_step}")
except SdkException as e:
    print(f"Error: {e}")

Description

Calculates the minimum wavelength increment supported by the system for a given wavelength range. Important for scan planning.

Parameters

  • group (int) - Component group number

  • start_wl (float) - Starting wavelength for the range in nanometers

  • stop_wl (float) - Ending wavelength for the range in nanometers

Returns

min_step (````): Minimum wavelength step size in nanometers

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_max_bw

DLL versions 4.4.13 and above

Get the maximum bandwidth for a wavelength range.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    group = 1
    start_wl = 400.0
    stop_wl = 800.0

    bandwidth = hw.get_max_bw(group, start_wl, stop_wl)
    print(f"bandwidth: {bandwidth}")
except SdkException as e:
    print(f"Error: {e}")

Description

Calculates the maximum spectral bandwidth (slit width equivalent) available for a given wavelength range.

Parameters

  • group (int) - Component group number

  • start_wl (float) - Starting wavelength for the range in nanometers

  • stop_wl (float) - Ending wavelength for the range in nanometers

Returns

bandwidth (````): Spectral bandwidth value

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_no_of_dark_currents

DLL versions 4.4.13 and above

Get the number of dark current calibration points.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    NoOfValues = hw.get_no_of_dark_currents()
    print(f"NoOfValues: {NoOfValues}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the count of wavelength points in the dark current calibration table for the current group.

Returns

NoOfValues (````): Number of calibration values in the arrays

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_n_groups

DLL versions 4.4.13 and above

Get the total number of component groups.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    n = hw.get_n_groups()
    print(f"n: {n}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the count of all component groups that have been created.

Returns

n (````): Group number or count value

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.get_zero_calibration_info

DLL versions 4.4.13 and above

Get zero calibration data for current group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    result = hw.get_zero_calibration_info()
    print(f"wavelength: {result.wavelength}")
    print(f"DarkCurrent: {result.DarkCurrent}")
except SdkException as e:
    print(f"Error: {e}")

Description

Retrieves wavelength, dark current, and Analogue-digital Converter (ADC) offset arrays from the zero calibration table. Arrays must be pre-allocated based on the count from get_no_of_dark_currents.

Returns

A BI_get_zero_calibration_info_result object containing:

  • wavelength (````): Wavelength value in nanometers

  • DarkCurrent (````): Array of dark current calibration values

  • ADCOffset (````): Array of ADC offset calibration values

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.group_add

DLL versions 4.4.13 and above

Add a component to a group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    n = 1

    hw.group_add(id, n)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Adds a component (by ID) to an existing group. Components in a group can be controlled together.

Parameters

  • id (str) - Component identifier string

  • n (int) - Group number or count value

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.group_remove

DLL versions 4.4.13 and above

Remove a component from a group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    n = 1

    hw.group_remove(id, n)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Removes a component (by ID) from a group.

Parameters

  • id (str) - Component identifier string

  • n (int) - Group number or count value

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.initialise

DLL versions 4.4.13 and above

Initialize the hardware system.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.initialise()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Initializes all hardware components for the current group. Must be called after build_system_model and before taking measurements. This homes monochromators and sets up detectors. The system must be initialized before measurements can be taken.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.load_setup

DLL versions 4.4.13 and above

Load component settings from a setup file.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    filename = "config.cfg"

    hw.load_setup(filename)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Loads previously saved component configurations from a setup file. This restores settings like wavelengths, gains, and other parameters.

Parameters

  • filename (str) - Path to the configuration or setup file

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.measurement

DLL versions 4.4.13 and above

Take a measurement without autoranging.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    reading = hw.measurement()
    print(f"reading: {reading}")
except SdkException as e:
    print(f"Error: {e}")

Description

Takes a reading from the detector at the current settings. Unlike automeasure, this does not adjust the gain. Negative values are clamped to zero unless AllowNegative is set. This function returns the reading at the current wavelength for the active group.

Returns

reading (````): Measurement reading value or array

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_automeasure

DLL versions 4.4.13 and above

Take measurements from all groups with autoranging.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    reading = hw.multi_automeasure()
    print(f"reading: {reading}")
except SdkException as e:
    print(f"Error: {e}")

Description

Performs automeasure on all component groups simultaneously. Returns an array of readings, one per group. Array must be pre-allocated.

Returns

reading (````): Measurement reading value or array

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_autorange

DLL versions 4.4.13 and above

Auto-range all groups simultaneously.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.multi_autorange()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Adjusts the amplifier ranges for all component groups at the same time.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_get_no_of_dark_currents

DLL versions 4.4.13 and above

Get dark current calibration point count for a specific group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    group = 1

    NoOfValues = hw.multi_get_no_of_dark_currents(group)
    print(f"NoOfValues: {NoOfValues}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the number of wavelength points in the dark current calibration table for the specified group.

Parameters

  • group (int) - Component group number

Returns

NoOfValues (````): Number of calibration values in the arrays

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_get_zero_calibration_info

DLL versions 4.4.13 and above

Get zero calibration data for a specific group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    group = 1

    result = hw.multi_get_zero_calibration_info(group)
    print(f"wavelength: {result.wavelength}")
    print(f"DarkCurrent: {result.DarkCurrent}")
except SdkException as e:
    print(f"Error: {e}")

Description

Retrieves wavelength, dark current, and ADC offset arrays for the specified group. Arrays must be pre-allocated.

Parameters

  • group (int) - Component group number

Returns

A BI_multi_get_zero_calibration_info_result object containing:

  • wavelength (````): Wavelength value in nanometers

  • DarkCurrent (````): Array of dark current calibration values

  • ADCOffset (````): Array of ADC offset calibration values

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_initialise

DLL versions 4.4.13 and above

Initialize all groups simultaneously.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.multi_initialise()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Initializes hardware for all component groups at the same time. Faster than initializing each group separately.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_measurement

DLL versions 4.4.13 and above

Take measurements from all groups.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    reading = hw.multi_measurement()
    print(f"reading: {reading}")
except SdkException as e:
    print(f"Error: {e}")

Description

Takes readings from all component groups simultaneously. Returns an array of readings. Array must be pre-allocated.

Returns

reading (````): Measurement reading value or array

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_park

DLL versions 4.4.13 and above

Park all monochromators in all groups.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.multi_park()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Moves all monochromators to their park positions across all groups simultaneously.

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_select_wavelength

DLL versions 4.4.13 and above

Set wavelength for all groups simultaneously.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    wavelength = 550.0

    settle_delay = hw.multi_select_wavelength(wavelength)
    print(f"settle_delay: {settle_delay}")
except SdkException as e:
    print(f"Error: {e}")

Description

Changes the wavelength for monochromators in all groups at the same time. Returns the maximum settle delay needed.

Parameters

  • wavelength (float) - Wavelength value in nanometers

Returns

settle_delay (````): Settle delay time in milliseconds after wavelength change

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.multi_zero_calibration

DLL versions 4.4.13 and above

Perform zero calibration across a wavelength range for all groups.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    start_wavelength = 400.0
    stop_wavelength = 800.0

    hw.multi_zero_calibration(start_wavelength, stop_wavelength)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Runs zero calibration (dark current and offset measurement) for all groups across the specified wavelength range.

Parameters

  • start_wavelength (float) - Starting wavelength for the range in nanometers

  • stop_wavelength (float) - Ending wavelength for the range in nanometers

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.park

DLL versions 4.4.13 and above

Park the monochromator in the current group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    hw.park()
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Moves the monochromator to its park position (usually a safe wavelength or home position).

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.read

DLL versions 4.4.13 and above

Read data from an anonymous device.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    buffer_size = 256
    id = "mono1"

    result = hw.read(buffer_size, id)
    print(f"buffer: {result.buffer}")
    print(f"chars_read: {result.chars_read}")
except SdkException as e:
    print(f"Error: {e}")

Description

Reads raw data from a device like an ADC or serial device. Buffer and size must be specified. Returns the actual number of characters read.

Parameters

  • buffer_size (int) - Size of the buffer in bytes

  • id (str) - Component identifier string

Returns

A BI_read_result object containing:

  • buffer (````): Buffer for reading or writing data

  • chars_read (````): Number of characters actually read

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.report_error

DLL versions 4.4.13 and above

Get the last error code.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    error_code = hw.report_error()
    print(f"error_code: {error_code}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the most recent error code from hardware operations. Use this to get detailed error information after a function returns an error. See error code definitions for meanings. Calling report_error clears the error code, i.e. subsequent calls will return no error (0) until another hardware error occurs.

Returns

error_code (````): Error code

Exceptions

Raises SdkException on failure.


BenHW.save_setup

DLL versions 4.4.13 and above

Save current component settings to a file.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    filename = "config.cfg"

    hw.save_setup(filename)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Saves the current configuration of all components to a setup file. This includes wavelengths, gains, and other settings that can be restored with load_setup.

Parameters

  • filename (str) - Path to the configuration or setup file

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.select_wavelength

DLL versions 4.4.13 and above

Set the wavelength for the current group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    wl = 550.0

    settle_delay = hw.select_wavelength(wl)
    print(f"settle_delay: {settle_delay}")
except SdkException as e:
    print(f"Error: {e}")

Description

Changes the wavelength of monochromators in the current group. Returns the settle delay time needed before taking measurements. The DLL will coordinate the operation of gratings, filter wheels, and SAMs to achieve the target wavelength.

Parameters

  • wl (float) - Wavelength value in nanometers

Returns

settle_delay (````): Settle delay time in milliseconds after wavelength change

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.send

DLL versions 4.4.13 and above

Send a command to an anonymous device.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    msg = "*IDN?"
    id = "mono1"

    hw.send(msg, id)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Sends a raw command string to a device like a serial instrument or controller.

Parameters

  • msg (str) - Message string to send or query

  • id (str) - Component identifier string

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.set

DLL versions 4.4.13 and above

Set a numeric attribute value for a component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    token = 10
    index = 0
    value = 1.0

    hw.set(id, token, index, value)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Sets a numeric (double) attribute on a hardware component. Use tokens to specify which attribute to set. The index parameter is used for multi-value attributes (usually 0).

Parameters

  • id (str) - Component identifier string

  • token (int) - Token identifier for the attribute to access

  • index (int) - Index for multi-value attributes (usually 0 for single values)

  • value (float) - Numeric value to set or retrieve

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.

  • InvalidAttributeException: The function was passed an attribute token referring to an attribute that does not exist or is inaccessible for the specified component.

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.

  • InvalidTokenException: The function was passed an invalid attribute token that is not recognized.


BenHW.set_str

DLL versions 4.4.13 and above

Set a string attribute value for a component.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    token = 10
    index = 0
    s = "mono1"

    hw.set_str(id, token, index, s)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Sets a string attribute on a hardware component. Use tokens to specify which attribute to set.

Parameters

  • id (str) - Component identifier string

  • token (int) - Token identifier for the attribute to access

  • index (int) - Index for multi-value attributes (usually 0 for single values)

  • s (str) - String value or buffer for text data

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.

  • InvalidAttributeException: The function was passed an attribute token referring to an attribute that does not exist or is inaccessible for the specified component.

  • InvalidComponentException: The function was passed a component identifier that does not exist in the system model.

  • InvalidTokenException: The function was passed an invalid attribute token that is not recognized.


BenHW.start_log

DLL versions 4.4.13 and above

Start logging for specified components.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    c_list = "mono1,adc1"

    hw.start_log(c_list)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Begins accumulating log messages for the specified comma-separated list of component IDs. Useful for debugging and diagnostics.

Parameters

  • c_list (str) - Comma-separated list of component IDs

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.stop_log

DLL versions 4.4.13 and above

Stop logging for specified components.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    c_list = "mono1,adc1"

    hw.stop_log(c_list)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Stops accumulating log messages for the specified components.

Parameters

  • c_list (str) - Comma-separated list of component IDs

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.trace

DLL versions 4.4.13 and above

Enable or disable trace logging.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    i = 1
    LoggingDir = "logs"

    hw.trace(i, LoggingDir)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Controls detailed trace logging to file. Pass 1 to enable and provide a logging directory, or 0 to disable. Trace logs are very detailed and useful for troubleshooting hardware communication issues and debugging applications.

Parameters

  • i (int) - Integer flag or control value (0=off, 1=on)

  • LoggingDir (str) - Directory path for logging output

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.Mapped_Logging

DLL versions 4.4.13 and above

Enable or disable mapped logging.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    i = 1

    hw.Mapped_Logging(i)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Controls whether motor position logging uses mapped values. Pass 1 to enable, 0 to disable.

Parameters

  • i (int) - Integer flag or control value (0=off, 1=on)

Exceptions

Raises SdkException on failure.


BenHW.use_group

DLL versions 4.4.13 and above

Set the current active group.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    n = 1

    hw.use_group(n)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Changes which component group is active. Subsequent operations will apply to this group.

Parameters

  • n (int) - Group number or count value

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.version

DLL versions 4.4.13 and above

Get the DLL version string.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    s = hw.version()
    print(f"s: {s}")
except SdkException as e:
    print(f"Error: {e}")

Description

Returns the version of the BenHW DLL as a string (e.g., ‘v4.12.0 (32 bit)’). Buffer must be pre-allocated with sufficient space (256 characters recommended).

Returns

s (````): String value or buffer for text data

Exceptions

Raises SdkException on failure.


BenHW.zero_calibration

DLL versions 4.4.13 and above

Perform zero calibration across a wavelength range.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    start_wl = 400.0
    stop_wl = 800.0

    hw.zero_calibration(start_wl, stop_wl)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Runs zero calibration (dark current and offset measurement) for the current group across the specified wavelength range. Essential for accurate measurements. The system should be in darkness or the shutter closed during this operation.

Parameters

  • start_wl (float) - Starting wavelength for the range in nanometers

  • stop_wl (float) - Ending wavelength for the range in nanometers

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.SCPI_query

DLL versions 4.4.13 and above

Send a SCPI query command and read response.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    id = "mono1"
    msg = "*IDN?"
    reply_size = 256

    reply = hw.SCPI_query(id, msg, reply_size)
    print(f"reply: {reply}")
except SdkException as e:
    print(f"Error: {e}")

Description

Sends a SCPI (Standard Commands for Programmable Instruments) query to a USB SCPI device and reads the response. Buffer size must be specified.

Parameters

  • id (str) - Component identifier string

  • msg (str) - Message string to send or query

  • reply_size (int) - Maximum size of reply buffer in bytes

Returns

reply (````): Buffer to receive reply data

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.


BenHW.SCPI_write

DLL versions 4.4.13 and above

Send a SCPI write command.

Example

from benhw import BenHW, tokens, SdkException

hw = BenHW()

try:
    msg = "*IDN?"
    id = "mono1"

    hw.SCPI_write(msg, id)
    print("Success")
except SdkException as e:
    print(f"Error: {e}")

Description

Sends a SCPI (Standard Commands for Programmable Instruments) command to a USB SCPI device without expecting a response.

Parameters

  • msg (str) - Message string to send or query

  • id (str) - Component identifier string

Exceptions

Raises SdkException on failure. The following derivative exceptions may be raised due to failure originating in BenHW dll:

  • BenHWException: Function call failed. Use BI_report_error to get detailed hardware error code.