NIHSDIO_ATTR_HWC_HARDWARE_COMPARE_MODE
Specific Attribute
| Data type |
Access | Applies to | Coercion | High-Level Functions |
|---|---|---|---|---|
| ViIn32 | R/W | None | None | None |
Description
Configures the device to compare expected data and actual data in real-time. This attribute must be set to the same value in both sessions.
 |
Note To use this feature you must have an acquisition and a generation session running concurrently. |
When you set this attribute to either NIHSDIO_VAL_HWC_STIMULUS_AND_EXPECTED_RESPONSE or NIHSDIO_VAL_HWC_EXPECTED_RESPONSE_ONLY, the generation engine sends expected data to the acquisition session to compare against acquired data.
Use the niHSDIO_WriteNamedWaveformWDT function to write expected data to the device. The device drives any values of 0, 1, or Z in the waveform, while values of H, L, or X are treated as expected data values.
This property must be set before data is written to the device.
| NIHSDIO_VAL_HWC_DISABLED (77) | Comparison engine is disabled. Any attempts to write expected response data to the device results in an error. |
| NIHSDIO_VAL_HWC_STIMULUS_AND_EXPECTED_RESPONSE (78) | Device drives and compares data in the same session. You can download waveforms with drive and/or compare data. All digital states are supported in this mode. |
| NIHSDIO_VAL_HWC_EXPECTED_RESPONSE_ONLY (79) | Device does not drive any data, it only acquires and compares. You cannot download drive data. A generation session downloads the expected waveform. Selecting this value pauses the generation lines to synchronize the acquisition and generation sessions. |