Appendix B
Register-Level Programming — Programming
PCI-DIO-96/PXI-6508/PCI-6503 User Manual
B-18
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Mode 0—Basic I/O
Use mode 0 for simple I/O functions (no handshaking) for each of the three ports and assign
each port as an input or an output port. Table B-4 shows the 16 possible I/O configurations.
Notice that programming the mode of operation for each port sets bit 7 of the control word.
Table B-4.
Mode 0 I/O Configurations
Number
Control Word
Bit 76543210
Group A
Group B
Port A
Port C
†
Port B
Port C
‡
0
10000000
Output
Output
Output
Output
1
10000001
Output
Output
Output
Input
2
10000010
Output
Output
Input
Output
3
10000011
Output
Output
Input
Input
4
10001000
Output
Input
Output
Output
5
10001001
Output
Input
Output
Input
6
10001010
Output
Input
Input
Output
7
10001011
Output
Input
Input
Input
8
10010000
Input
Output
Output
Output
9
10010001
Input
Output
Output
Input
10
10010010
Input
Output
Input
Output
11
10010011
Input
Output
Input
Input
12
10011000
Input
Input
Output
Output
13
10011001
Input
Input
Output
Input
14
10011010
Input
Input
Input
Output
15
10011011
Input
Input
Input
Input
†
Upper nibble of port C
‡
Lower nibble of port C
