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Contents
PCI-DIO-96/PXI-6508/PCI-6503 User Manual
vi
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Mode 1 Input Timing ...................................................................................... 4-5
Mode 1 Output Timing ................................................................................... 4-6
Mode 2 Bidirectional Timing.......................................................................... 4-7
Appendix B
Register-Level Programming
82C53 Programmable Interval Timer (PCI-DIO-96, PXI-6508 Only) ......................... B-2
Introduction ..................................................................................................... B-4
Register Map ................................................................................................... B-5
Register Descriptions ...................................................................................... B-6
Register Description Format............................................................. B-6
Register Description for the 82C55A ............................................... B-6
Register Description for the 82C53
(PCI-DIO-96, PXI-6508 Only) ...................................................... B-9
Register Description for the Interrupt Control Registers.................. B-10
Interrupt Control Register 1.............................................................. B-10
Interrupt Control Register 2.............................................................. B-12
Interrupt Clear Register (PCI-DIO-96, PXI-6508 Only).................. B-13
Programming Considerations for the 82C55A................................................ B-17
Modes of Operation .......................................................................... B-17
Mode 0—Basic I/O........................................................................... B-18
Mode 1—Strobed Input .................................................................... B-19
Port C Status-Word Bit Definitions for Input (Ports A and B) ........ B-21
Mode 1—Strobed Output ................................................................. B-23
Port C Status-Word Bit Definitions for Output (Ports A and B)...... B-24
Mode 2—Bidirectional Bus.............................................................. B-26