Configuring the Initial Line Direction for the NI 9401 (FPGA Interface)

Each digital port on the NI 9401 is initially configured as a digital input. You can configure the initial line direction for each port on the NI 9401 at edit time using the C Series Module Properties dialog box. You can programmatically change the line direction for each port at run time using the FPGA I/O Method Node. The execution of an I/O Method Node that is configured with a Set Line Direction method overwrites the value you configured in the C Series Module Properties dialog box.

Configuring Line Direction Using the C Series Module Properties Dialog Box

Complete the following steps to configure the line direction of each digital port using the C Series Module Properties dialog box.

1. Configure the CompactRIO system, and add an NI 9401.
2. Right-click the NI 9401 in the Project Explorer window and select Properties from the shortcut menu to display the C Series Module Properties dialog box.
3. Select the direction for each port from the Initial Line Direction pull-down menus.
4. Click the OK button.
5. Select File»Save All in the Project Explorer window.

Configuring Line Direction Using the FPGA I/O Method Node

Complete the following steps to configure the line direction of each digital port using the FPGA I/O Method Node.

1. Place an FPGA I/O Method Node on the block diagram and configure it for the NI 9401.
2. Click the Method section and select the Set Line Direction method from the shortcut menu.
3. Right-click each digital port input and select Create»Control from the shortcut menu.
4. On the front panel of the VI, select the direction for each port from the digital port pull-down menus.