Appendix B
Register-Level Programming — Programming
PCI-DIO-96/PXI-6508/PCI-6503 User Manual
B-20
ni.com
Figure B-5 shows the control word written to the Configuration Register to configure port B
for input in mode 1. Notice that port B does not have extra input or output lines left from
port C when ports A and B are both enabled for handshaking.
Figure B-5.
Control Word to Configure Port B for Mode 1 Input
During a mode 1 data read transfer, read port C to obtain the status of the handshaking lines
and interrupt signals. Refer to the
Port C Status-Word Bit Definitions for Input (Ports A
Port C Status-Word Bit Definitions for Output (Ports A and B)
section,
Port C Status-Word Bit Definitions for Bidirectional Data Path (Port A Only)
section
for detailed definitions.
D7
D6
D5
D4
D3
D2
D1
D0
1
X
X
X
X
1
X
1