Setting Properties and Attributes Before Reading Them

Properties and attributes are modified when you set them or when you call a configuration VI or function that sets them, respectively. It is important to set the properties or attributes or call any configuration VIs or functions before reading back any property or attribute values for the following reasons:

• Values read are coerced depending on the current configuration of the session. If you read a property or attribute value and then set other properties or attributes, the value read may no longer be valid.
• The driver verifies that the configuration of the device is valid at the time the property or attribute is read. It is possible to get an error when reading a property or attribute if the configuration is not valid at that point, even when a setting later could make it valid.
• Reading properties or attributes causes the driver to verify the current configuration. If you change some of the settings later, those settings need to be validated again.

Note  Perform all module configuration before writing data on output devices.