NIHSDIO_ATTR_SUPPORTED_DATA_STATES
- Updated2023-02-21
- 3 minute(s) read
Specific Attribute
| Data type |
Access | Applies to | Coercion | High-Level Functions |
|---|---|---|---|---|
| ViIn32 | R/W | None | None | None |
Description
Configures the supported digital data states in a waveform. Use this attribute to enable tristate data generation or real-time hardware compare data. To use the hardware comparison feature you must have an acquisition and a generation session running concurrently. When you select hardware compare data, you must set this attribute to the same value in both sessions.
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Note For NI 6547/6548 devices, when you set this attribute to an extended data mode it reduces the number of channels available for dynamic generation to 24. The top eight channels (24 to 31) are available for dynamic acquisition or static generation, and the lower twenty-four channels (0 to 23) are available for dynamic generation of supported data states. |
When you set this attribute to NIHSDIO_VAL_STATES_L_H_X, all data is configured for comparison. When you set this attribute to NIHSDIO_VAL_STATES_0_1_Z_L_H_X, the software is configured for either driving generation data or comparing 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.
You must set this attribute before you write data or allocate a waveform on the device.
| NIHSDIO_VAL_STATES_0_1 (77) | Configures the device to support binary data only. Does not allow tristate or expected data. Disables the comparison engine. NI-HSDIO returns an error if you try to write expected response or tristate data to the device while configured to this value. |
| NIHSDIO_VAL_STATES_0_1_Z (83) | Configures the device to support binary and tristate (Z state) data. Disables the comparison engine. NI-HSDIO returns an error if you try to write expected response data to the device while configured to this value. You must set this value before you can write a waveform with per cycle tristate. Ignore this value for acquisition sessions. |
| NIHSDIO_VAL_STATES_0_1_Z_L_H_X (78) | Configures the device to support binary, tristate, and expected data. 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_STATES_L_H_X (79) | Configures the device to only acquire and compare data. 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. |
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Note This attribute replaces the obsoleted NIHSDIO_ATTR_HWC_HARDWARE_COMPARE_MODE attribute. Refer to the following table for the relative values of each attribute. |
| Supported Data States Value | Hardware Compare Mode Value (obsolete) |
|---|---|
| NIHSDIO_VAL_STATES_0_1 | NIHSDIO_VAL_HWC_DISABLED |
| NIHSDIO_VAL_STATES_0_1_Z | N/A |
| NIHSDIO_VAL_STATES_L_H_X | NIHSDIO_VAL_HWC_EXPECTED_RESPONSE_ONLY |
| NIHSDIO_VAL_STATES_0_1_Z_L_H_X | NIHSDIO_VAL_HWC_STIMULUS_AND_EXPECTED_RESPONSE |