Contec I/O Interface for Contec digital I/O devices

Interface:	Contec
Revision:	24.11.4
Date:	2026-09-23

General

This page provides the documentation of the HALCON Contec interface for accessing the Contec Digital I/O cards. Only interface specific parameters and features are described here. For general information of the operators for I/O interfaces please have a look at the HALCON Operator Reference.
Registered customers can download the latest revision of this interface from the MVTec WWW server.

System Requirements

Intel compatible PC with Windows 7 (32-bit or 64-bit) or newer that is also supported by the vendor-specific SDK, also WoW64 (using 32-bit HALCON on 64-bit Windows).
Installed Contec Runtime with version 4.4. (or higher). The CDIO.dll must be found within you search path.
Windows: HALCON I/O interface hioContec.dll or hioContecxl.dll, respectively. If you have properly installed the interface, all these DLLs should reside in bin\%HALCONARCH% within the HALCON base directory %HALCONROOT% you have chosen during the installation of HALCON.

Installation

Only when installing or updating the interface manually follow these steps:

Extract the archive containing the interface files to the HALCON base directory %HALCONROOT% (Note: Administrator privileges may be required for this step). Additionally, you have to move the interface examples to the directory %HALCONEXAMPLES% manually.

Features

Opening and using of multiple Contec I/O ports.
Opening and using of multiple specific channels (specific port values).
Support of digital inputs and digital outputs.

Limitations

No support of counters.
No support of analog functions.
No support of bi-directional I/O channels.

Operator control_io_interface

Not supported by this interface.

Operator query_io_interface

query_io_interface(::IOInterfaceName, Query:Result)

Query information about the specified I/O device interface.

Parameter	Values	Type	Description
IOInterfaceName	'Contec'	string	HALCON I/O interface name.
Query		string	Parameter name of the query.
'io_device_names'		string	Returns a list of available devices.
'param_name'		string	Returns the possible parameter names.
'revision'		string	Revision number of the Contect interface.
Result		integer, real, string	List of result values (according to Query).

Operator open_io_device

open_io_device(::IOInterfaceName, IODeviceName, GenParamName, GenParamValue:IODeviceHandle)

Open and configure an I/O device.

Parameter	Values	Default	Type	Description
IOInterfaceName	'Contec'	[]	string	HALCON I/O interface name.
IODeviceName		[]	string	I/O device name.
GenParamName		[]	string	Dynamic parameter names.
GenParamValue		[]	integer, real, string	Dynamic parameter values.
IODeviceHandle			handle	Handle of the opened I/O device.

Operator control_io_device

Not supported by this interface.

Operator set_io_device_param

Set the device parameters. Currently, no parameters are defined.

Operator get_io_device_param

get_io_device_param(::IODeviceHandle, GenParamName:GenParamValue)

Query settings of an I/O device instance.

There may exist additional parameter attributes, which can be accessed as 'ParamNames.AttributeName'. The following standard attributes may be available:

'.access': This attribute provides the access permissions of the corresponding parameter as a string. Possible values are 'ro' (read-only), 'wo' (write-only), 'rw' (read/write), 'na' (unavailable, perhaps due to insufficient access rights), and 'ni' (unavailable, not defined for this device or channel).
'.category': This attribute provides the category of the corresponding parameter as a string. 'I/O interface' for all pre-defined I/O interface parameters.
'.default': This attribute provides the default value of the corresponding parameter.
'.description': This attribute provides the description of the corresponding parameter as a string.
'.displayname': This attribute provides the displayname of the corresponding parameter as a string.
'.range': This attribute provides the minimum and maximum, (and the step width, if applicable) for the corresponding integer or float parameter as a tuple with 2 (or 3) elements.
'.representation': This attribute provides how the value of the parameter should be displayed in a GUI: 'ip address', 'hex', ...
'.tooltip': This attribute provides the tool-tip of the corresponding parameter as a string.
'.type': This attribute provides the HALCON value type (integer, real, or string) of the corresponding parameter as a string.
'.values': This attribute provides the valid value list for the corresponding parameter as a tuple.
'.visibility': This attribute provides the visibility of the corresponding parameter as a string. Possible values are 'common', 'extended', and 'dangerous'.
'.unit': This attribute provides the units of the corresponding parameter as a string. For example: 'ns', 'us' and 'ms', or 'mm', 'cm', 'dm' and 'm'.

Parameter	Type	Description
IODeviceHandle	handle	Handle of the opened I/O device.
GenParamName	string	Parameter names.
'io_device_name'	string	Returns the name of the device.
'param_name'	string	Returns the possible parameter names.
GenParamValue	integer, real, string, handle	Parameter values.

Operator query_io_device

query_io_device(::IODeviceHandle, IOChannelName, Query:Result)

Query information about channels of the specified I/O device.

Parameter	Values	Type	Description
IODeviceHandle		handle	Handle of the opened I/O device.
IOChannelName		string	Channel names to query.
Query		string	Name of the query.
'channel_type'	'digital_input', 'digital_output'	string	Returns the type of a channel.
'io_channel_names'		string	Returns a list of channels provided by the device e.g. 'di_0.2' describes input port channel 2 on port 0. To list only the channels of a specific type, use the special form io_channel_names.<channel_type> (for a list of valid channel types, see the description of the channel_type parameter).
'param_name'		string	Returns the possible parameter names.
'value.range'	[<min>,<max>,<step>]	string	Return the possible range of the used I/O channel name parameter
Result		integer, real, string	List of values (according to Query).

Operator open_io_channel

open_io_channel(::IODeviceHandle, IOChannelName, GenParamName, GenParamValue:IOChannelHandle)

Open and configure I/O channels.

Parameter	Default	Type	Description
IODeviceHandle		handle	Handle of the opened I/O device.
IOChannelName		string	HALCON I/O channel names of the specified device.
GenParamName	[]	string	Parameter names.
GenParamValue	[]	integer, real, string	Parameter values.
IOChannelHandle		handle	Handles of the opened I/O channel.

Operator control_io_channel

Not supported by this interface.

Operator set_io_channel_param

Not supported by this interface.

Operator get_io_channel_param

get_io_channel_param(::IOChannelHandle, GenParamName:GenParamValue)

Query specific parameters of I/O channels.

There may exist additional parameter attributes, which can be accessed as 'ParamNames.AttributeName'. The following standard attributes may be available:

'.access': This attribute provides the access permissions of the corresponding parameter as a string. Possible values are 'ro' (read-only), 'wo' (write-only), 'rw' (read/write), 'na' (unavailable, perhaps due to insufficient access rights), and 'ni' (unavailable, not defined for this device or channel).
'.category': This attribute provides the category of the corresponding parameter as a string. 'I/O interface' for all pre-defined I/O interface parameters.
'.default': This attribute provides the default value of the corresponding parameter.
'.description': This attribute provides the description of the corresponding parameter as a string.
'.displayname': This attribute provides the displayname of the corresponding parameter as a string.
'.range': This attribute provides the minimum and maximum, (and the step width, if applicable) for the corresponding integer or float parameter as a tuple with 2 (or 3) elements.
'.representation': This attribute provides how the value of the parameter should be displayed in a GUI: 'ip address', 'hex', ...
'.tooltip': This attribute provides the tool-tip of the corresponding parameter as a string.
'.type': This attribute provides the HALCON value type (integer, real, or string) of the corresponding parameter as a string.
'.values': This attribute provides the valid value list for the corresponding parameter as a tuple.
'.visibility': This attribute provides the visibility of the corresponding parameter as a string. Possible values are 'common', 'extended', and 'dangerous'.
'.unit': This attribute provides the units of the corresponding parameter as a string. For example: 'ns', 'us' and 'ms', or 'mm', 'cm', 'dm' and 'm'.

Parameter	Type	Description
IOChannelHandle	handle	Handles of the opened I/O channels.
GenParamName	string	Parameter names.
'io_channel_name'	string	Returns the name of the channel.
'param_name'	string	Returns the possible parameter names.
GenParamValue	integer, real, string, handle	Parameter values.

Operator read_io_channel

read_io_channel(::IOChannelHandle:Value, Status)

Read a value from the specified I/O channels.

Parameter	Type	Description
IOChannelHandle	handle	Handles of the opened I/O channels.
Value	integer, real, string, handle	Read value.
Status	integer	Status of read value. A status of '0' indicates success, while any other value indicates an error condition.

Operator write_io_channel

write_io_channel(::IOChannelHandle, Value:Status)

Write a value to a specific io channel. If several handles are passed, the data of each handle will be written internally to the associated channel.

Parameter	Type	Description
IOChannelHandle	handle	Handles of the opened I/O channels.
Value	integer, real, string, handle	Write values.
Status	integer	Status of written values. A status of '0' indicates success, while any other value indicates an error condition.

Operator close_io_channel

close_io_channel(::IOChannelHandle:)

Close I/O channels.

Parameter	Type	Description
IOChannelHandle	handle	Handles of the opened I/O channels.

Operator close_io_device

close_io_device(::IODeviceHandle:)

Close the specified I/O device.

Parameter	Type	Description
IODeviceHandle	handle	Handle of the opened I/O device.

Query the requested information from the specified I/O channels. The parameter 'ParameterNode' is not used by this interface.

HDevelop Examples

For this interface the following examples are available:

contec_digital_read.hdev - Example to show how to read several parameters and values.
contec_digital_write.hdev - Example to show how to write serveral parameters and values.

Release Notes

Revision 24.11.4 (Sep 23, 2026):
- Minor bug fixes.
- A Software Bill of Materials (SBOM) in the System Package Data Exchange (SPDX) format has been added next to each binary file with the same name extended by ".spdx.json".
Revision 20.11.3 (Aug 1, 2023):
- Extended error messages are now available in case an operation failes. This allows to get information about the root cause.
- The distribution package of this interface now contains files providing meta information for the HDevelop example browser.
Revision 13.0.2 (Nov 28, 2017):
- The technical dependency from the HALCON Library has been removed.
Revision 13.0.1 (Oct 28, 2016):
- HALCON 13 version of the interface.
Revision 1.1 Addendum (Sep 9, 2015):
- Bi-directional I/O channels are not supported. A note has been added to the 'Limitations' section.
- The HDevelop examples contec_digital_read.hdev and contec_digital_write.hdev have been improved.
Revision 1.1 (Jan 1, 2015):
- Fixed queries of 'param_name' in query_io_interface, query_io_device, and get_io_channel_param.
- Fixed query of 'channel_type' in query_io_interface.
- Extended description of 'io_channel_names'.
- Added values for 'channel_type'.
Revision 1.0 (May 26, 2014):
- First official release.

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