niDCPower_SetAttributeViBoolean
ViStatus niDCPower_SetAttributeViBoolean(ViSession vi, ViConstString channelName, ViAttr attribute, ViBoolean value)
Purpose
Sets the value of a ViBoolean attribute.
This is a low-level function that you can use to set the values of device-specific attributes and inherent IVI attributes. If the attribute represents a device state, this function performs device I/O in the following cases:
- State caching is disabled for the entire session or for the particular attribute.
- State caching is enabled and the currently cached value is invalid or is different than the value you specify.
NI-DCPower contains high-level functions that set most of the device attributes. It is best to use the high-level driver functions as much as possible. They handle order dependencies and multithread locking for you. In addition, they perform status checking only after setting all of the attributes. In contrast, when you set multiple attributes using the SetAttribute functions, this function checks the device status after each call. Also, when state caching is enabled, the high-level functions that configure multiple attributes perform device I/O only for the attributes whose value you change. Thus, you can safely call the high-level functions without the penalty of redundant device I/O.
Parameters
Input | ||||
Name | Type | Description | ||
vi | ViSession | Identifies a particular instrument session. vi is obtained from the niDCPower_init or niDCPower_InitWithOptions function. | ||
channelName | ViConstString | If the attribute is channel-based, this attribute specifies the name of the channel on which to set the value of the attribute. If the attribute is not channel-based, then pass VI_NULL or an empty string. Valid channel names are 0, 1, and 2. | ||
attribute | ViAttr | Specifies the ID of an attribute. From the function panel window, you can use this control as follows.
|
||
value | ViBoolean | Specifies the value to which you want to set the attribute. If the attribute currently showing in the attribute ring control has constants as valid values, you can view a list of the constants by pressing Enter on this control. Select a value by double-clicking on it or by selecting it and then pressing Enter.
|
Return Value
Name | Type | Description |
Status | ViStatus | Reports the status of this operation. To obtain a text description of the status code, call the niDCPower_error_message function. To obtain additional information concerning the error condition, call the niDCPower_GetError function. |