National Instruments 5411 - Manual (Page 21)

Chapter 3 Signal Connections
DAQArb 5411 User Manual 3-4 © National Instruments Corporation
If no external reference clock is available, the DAQArb 5411 will
automatically tune the internal clock to the best accuracy possible. For
more information on PLL operation, refer to Chapter 4, Arb Operation.
Dig Out Connector
Dig Out is a 16-bit digital I/O connector that contains the 16-bit digital
pattern outputs, digital pattern clock output, marker output, external
trigger input, and power output.
Connector Pin Assignments
Figure 3-4 shows the DAQArb 5411 50-pin digital connector.