DOChannel Class
- Updated2023-02-21
- 7 minute(s) read
DOChannel Class
Encapsulates one or more digital output channels and the properties for a digital output channel.
Inheritance Hierarchy
SystemObject
SystemMarshalByRefObject
NationalInstruments.DAQmxChannel
NationalInstruments.DAQmxDOChannel
SystemMarshalByRefObject
NationalInstruments.DAQmxChannel
NationalInstruments.DAQmxDOChannel
Namespace: NationalInstruments.DAQmx
Assembly: NationalInstruments.DAQmx (in NationalInstruments.DAQmx.dll) Version: 20.7.40.49302
Syntax
public class DOChannel : Channel, IFilteredTypeDescriptor
Public Class DOChannel Inherits Channel Implements IFilteredTypeDescriptor
The DOChannel type exposes the following members.
Properties
| Name | Description | |
|---|---|---|
 | DataTransferMechanism | Specifies the data transfer mode for the device. |
| DataTransferRequestCondition | Specifies under what condition to transfer data from the buffer to the onboard memory of the device. |
| Description | Specifies a user-defined description for the channel. (Inherited from Channel.) |
| GenerateOn | Specifies on which edge of the sample clock to generate samples. |
| InvertLines | Specifies whether to invert the lines in the channel. If you set this property to , the lines are at high logic when off and at low logic when on. |
| IsGlobal | Indicates whether the channel is a global channel. (Inherited from Channel.) |
| LineStatesDoneState | Specifies the state of the lines in a digital output task when the task completes execution. |
| LineStatesPausedState | Specifies the state of the lines in a digital output task when the task pauses. |
| LineStatesStartState | Specifies the state of the lines in a digital output task when the task starts. |
| LogicFamily | Specifies the logic family to use for generation. A logic family corresponds to voltage thresholds that are compatible with a group of voltage standards. Refer to the device documentation for information on the logic high and logic low voltages for these logic families. |
| MemoryMappingEnable | Specifies for NI-DAQmx to map hardware registers to the memory space of the application, if possible. Normally, NI-DAQmx maps hardware registers to memory accessible only to the kernel. Mapping the registers to the memory space of the application increases performance. However, if the application accesses the memory space mapped to the registers, it can adversely affect the operation of the device and possibly result in a system crash. |
| NumberOfLines | Indicates the number of digital lines in the channel. |
| OutputDriveType | Specifies the drive type for digital output channels. |
| OvercurrentAutoReenable | Specifies whether to automatically reenable channels after they no longer exceed the current limit specified by OvercurrentLimit. |
| OvercurrentLimit | Specifies the current threshold in Amperes for the channel. A value of 0 means the channel observes no limit. Devices can monitor only a finite number of current thresholds simultaneously. If you attempt to monitor additional thresholds, NI-DAQmx returns an error. |
| OvercurrentReenablePeriod | Specifies the delay in seconds between the time a channel no longer exceeds the current limit and the reactivation of that channel, if OvercurrentAutoReenable is . |
| PhysicalName | Specifies the name of the physical channel upon which this virtual channel is based. (Inherited from Channel.) |
| SynchronizationUnlockBehavior | Specifies the action to take if the target loses its synchronization to the grand master. (Inherited from Channel.) |
| Tristate | Specifies whether to stop driving the channel and set it to a high-impedance state. You must commit the task for this setting to take effect. |
| Type | Indicates the type of the virtual channel. (Inherited from Channel.) |
| UsbTransferRequestCount | Specifies the maximum number of simultaneous USB transfers used to stream data. Modify this value to affect performance under different combinations of operating system and device. |
| UsbTransferRequestSize | Specifies the maximum size of a USB transfer request in bytes. Modify this value to affect performance under different combinations of operating system and device. |
| UseOnlyOnBoardMemory | Specifies whether to write samples directly to the onboard memory of the device, bypassing the memory buffer. Generally, you cannot update onboard memory after you start the task. Onboard memory includes data FIFOs. |
| VirtualName | Gets the name of the virtual channel. (Inherited from Channel.) |
Methods
| Name | Description | |
|---|---|---|
 | CreateObjRef | Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object. (Inherited from MarshalByRefObject.) |
| Dispose | Releases all resources used by Channel. (Inherited from Channel.) |
 | Dispose(Boolean) |
Releases the managed and unmanaged resources used by Channel or optionally releases only the unmanaged resources.
(Inherited from Channel.) |
| Equals | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
| GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
| GetLifetimeService | Retrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject.) |
| GetType | Gets the Type of the current instance. (Inherited from Object.) |
| InitializeLifetimeService | Obtains a lifetime service object to control the lifetime policy for this instance. (Inherited from MarshalByRefObject.) |
| MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
| MemberwiseClone(Boolean) | Creates a shallow copy of the current MarshalByRefObject object. (Inherited from MarshalByRefObject.) |
| ToString | Returns a string representation of the object. (Inherited from Channel.) |
Remarks
Use the DOChannels property to create or access a digital output channel. A DOChannel might contain more than one virtual channel because the DOChannel is defined by providing a valid NI-DAQmx channel string to the DOChannels indexer or to a DOChannelCollection create channel method. If you set a property on a DOChannel object that represents multiple channels, that property is set for all of the channels that the object represents.
 Tip |
|---|
| Example applications are located in the Public Documents\National Instruments\NI-DAQ\Examples\DotNET4.x directory or in the Start menu at National InstrumentsNI-DAQmxNI-DAQmx Examples. |
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.