National Instruments 653X Manuale Utente

© National Instruments Corporation

To begin using your 653X device, navigate this chapter in the following 
order:

1.

Choose the correct mode of operation to perform using the table below.

2.

Follow the instructions for the application you want to perform.

3.

Refer to pinout diagrams in Appendix C, 

, when you are ready to connect your devices and/or 

accessories.

See the glossary for definitions to digital I/O terms used throughout this chapter.

Use the following table to find the correct mode for your application:

I need to perform basic digital I/O that does not need hardware timing or handshaking between 
the 653X and the peripheral device.

Unstrobed I/O

I want to configure the direction of each bit individually instead of groups of eight.

Unstrobed I/O

I want to connect two or more output drivers/pins to the same line.

Unstrobed output with 
wired-OR driver

I need to communicate with an external device using an exchange of signals to request and 
acknowledge each data transfer.

Handshaking I/O–
Select appropriate 
protocol

I want to start and/or stop acquiring data upon a trigger and/or to transfer data at timed intervals.

Pattern I/O

I want the 653X to capture input data only when certain lines change states.

Change Detection

I want to monitor activity on input lines without continuously polling or transferring 
unnecessary data during periods of inactivity.

Change Detection