| Data Acquisition Toolbox™ |   |
Base properties apply to all supported hardware subsystems of
a given type (analog input, analog output, or digital I/O). For example,
the SampleRate property is supported
for all analog input subsystems regardless of the vendor.
The properties are categorized according to these subsystems:
| Analog Input Properties | Analog input base properties are divided into two
main categories: common properties and channel properties. Common
properties apply to every channel contained by the analog input object,
while channel properties can be configured for individual channels. | | Analog Output Properties | Analog output base properties are divided into two
main categories: common properties and channel properties. Common
properties apply to every channel contained by the analog output object,
while channel properties can be configured for individual channels. | | Digital I/O Properties | Digital I/O base properties are divided into two main
categories: common properties and line properties. Common properties
apply to every line contained by the digital I/O object, while line
properties can be configured for individual lines. |
|
Depending on the hardware device you are using, additional property
names or property values might be present. The additional property
names are described in Device-Specific Properties — Alphabetical List. For example,
only analog input and analog output objects associated with a sound
card have a BitsPerSample property.
The additional property values are also device-specific but are included
in this chapter. For example, all supported devices have an InputType property, but the value AC-Coupled is
unique to analog input objects associated with a sound card.
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Analog Input Properties
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Common Properties
The analog input common properties are grouped into the following
categories based on usage.
Analog Input Basic Setup Properties
| SampleRate | Specify per-channel rate at which analog data is converted
to digital data, or vice versa |
| SamplesPerTrigger | Specify number of samples to acquire for each channel
group member for each trigger that occurs |
| TriggerType | Specify type of trigger to execute |
Analog Input Logging Properties
| LogFileName | Specify name of disk file information is logged to |
| Logging | Indicate whether data is being logged to memory or disk
file |
| LoggingMode | Specify destination for acquired data |
| LogToDiskMode | Specify whether data, events, and hardware information
are saved to one or more disk files |
Analog Input Trigger Properties
Analog Input Status Properties
| Logging | Indicate whether data is being logged to memory or disk
file |
| Running | Indicate whether device object is running |
| SamplesAcquired | Indicate number of samples acquired per channel |
| SamplesAvailable | Indicate number of samples available per channel in engine |
Analog Input Hardware Configuration Properties
| ChannelSkew | Specify time between consecutive scanned hardware channels |
| ChannelSkewMode | Specify how channel skew is determined |
| ClockSource | Specify clock that governs hardware conversion rate |
| InputType | Specify analog input hardware channel configuration |
| SampleRate | Specify per-channel rate at which analog data is converted
to digital data, or vice versa |
Analog Input Callback Properties
| DataMissedFcn | Specify M-file callback function to execute when data
is missed |
| InputOverRangeFcn | Specify M-file callback function to execute when acquired
data exceeds valid hardware range |
| RuntimeErrorFcn | Specify M-file callback function to execute when run-time
error occurs |
| SamplesAcquired | Indicate number of samples acquired per channel |
| SamplesAcquiredFcn | Specify M-file callback function to execute when predefined
number of samples is acquired for each channel group member |
| StartFcn | Specify M-file callback function to execute before device
object runs |
| StopFcn | Specify M-file callback function to execute after device
object runs |
| TimerFcn | Specify M-file callback function to execute when predefined
time period passes |
| TimerPeriod | Specify time period between timer events |
| TriggerFcn | Specify M-file callback function to execute when trigger
occurs |
Analog Input General Purpose Properties
| BufferingConfig | Specify per-channel allocated memory |
| BufferingMode | Specify how memory is allocated |
| Channel | Contain hardware channels added to device object |
| EventLog | Store information for specific events |
| Name | Specify descriptive name for device object |
| Tag | Specify device object label |
| Timeout | Specify additional waiting time to extract or queue data |
| Type | Indicate device object type, channel, or line |
| UserData | Store data to associate with device object |
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Channel Properties
The analog input channel properties are given below.
Analog Input Channel Properties
| ChannelName | Specify descriptive channel name |
| HwChannel | Specify hardware channel ID |
| HwLine | Specify hardware line ID |
| Index | MATLAB index of hardware channel or line |
| InputRange | Specify range of analog input subsystem |
| NativeOffset | Indicate offset to use when converting between native
data format and doubles |
| NativeScaling | Indicate scaling to use when converting between native
data format and doubles |
| Parent | Indicate parent (device object) of channel or line |
| SensorRange | Specify range of data expected from sensor |
| Type | Indicate device object type, channel, or line |
| Units | Specify engineering units label |
| UnitsRange | Specify range of data as engineering units |
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Analog Output Properties
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Common Properties
The analog output common properties are grouped into the following
categories based on usage.
Analog Output Basic Setup Properties
| SampleRate | Specify per-channel rate at which analog data is converted
to digital data, or vice versa |
| TriggerType | Specify type of trigger to execute |
Analog Output Trigger Properties
Analog Output Status Properties
| Running | Indicate whether device object is running |
| SamplesAvailable | Indicate number of samples available per channel in engine |
| SamplesOutput | Indicate number of samples output per channel from engine |
| Sending | Indicate whether data is being sent to hardware device |
Analog Output Hardware Configuration Properties
| ClockSource | Specify clock that governs hardware conversion rate |
| SampleRate | Specify per-channel rate at which analog data is converted
to digital data, or vice versa |
Analog Output Data Management Properties
| MaxSamplesQueued | Indicate maximum number of samples that can be queued
in engine |
| RepeatOutput | Specify number of additional times queued data is output |
| Timeout | Specify additional waiting time to extract or queue data |
Analog Output Callback Properties
| RuntimeErrorFcn | Specify M-file callback function to execute when run-time
error occurs |
| SamplesOutputFcn | Specify M-file callback function to execute when predefined
number of samples is output for each channel group member |
| SamplesOutputFcnCount | Specify number of samples to output for each channel group
member before samples output event is generated |
| StartFcn | Specify M-file callback function to execute before device
object runs |
| StopFcn | Specify M-file callback function to execute after device
object runs |
| TimerFcn | Specify M-file callback function to execute when predefined
time period passes |
| TimerPeriod | Specify time period between timer events |
| TriggerFcn | Specify M-file callback function to execute when trigger
occurs |
Analog Output General Purpose Properties
| BufferingConfig | Specify per-channel allocated memory |
| BufferingMode | Specify how memory is allocated |
| Channel | Contain hardware channels added to device object |
| EventLog | Store information for specific events |
| Name | Specify descriptive name for device object |
| OutOfDataMode | Specify how value held by analog output subsystem is determined |
| Tag | Specify device object label |
| Type | Indicate device object type, channel, or line |
| UserData | Store data to associate with device object |
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Channel Properties
The analog output channel properties are given below.
Analog Output Channel Properties
| ChannelName | Specify descriptive channel name |
| DefaultChannelValue | Specify value held by analog output subsystem |
| HwChannel | Specify hardware channel ID |
| Index | MATLAB index of hardware channel or line |
| NativeOffset | Indicate offset to use when converting between native
data format and doubles |
| NativeScaling | Indicate scaling to use when converting between native
data format and doubles |
| OutputRange | Specify range of analog output hardware subsystem |
| Parent | Indicate parent (device object) of channel or line |
| Type | Indicate device object type, channel, or line |
| Units | Specify engineering units label |
| UnitsRange | Specify range of data as engineering units |
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Digital I/O Properties
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Common Properties
The digital I/O common properties are given below.
Digital I/O Common Properties
| Line | Contain hardware lines added to device object |
| Name | Specify descriptive name for device object |
| Running | Indicate whether device object is running |
| Tag | Specify device object label |
| TimerFcn | Specify M-file callback function to execute when predefined
time period passes |
| TimerPeriod | Specify time period between timer events |
| Type | Indicate device object type, channel, or line |
| UserData | Store data to associate with device object |
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Line Properties
The digital I/O line properties are given below.
Digital I/O Line Properties
| Direction | Specify whether line is for input or output |
| HwLine | Specify hardware line ID |
| Index | MATLAB index of hardware channel or line |
| LineName | Specify descriptive line name |
| Parent | Indicate parent (device object) of channel or line |
| Port | Specify port ID |
| Type | Indicate device object type, channel, or line |
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Getting Command-Line Property Help
To get command-line property help, use the daqhelp function.
For example, to get help for the SampleRate property,
type:
daqhelp SampleRate
Note
You can use daqhelp without creating a device
object. |
You can also get property characteristics, such as the default
property value, using the propinfo function.
For example, suppose you create the analog input object ai for
a sound card and you want to find the default value for the SampleRate property.
ai = analoginput('winsound');
out = propinfo(ai,'SampleRate');
out.DefaultValue
ans =
8000
| wait | | Base Properties — Alphabetical List | |
Alphabetical List