PCI-1751U User Manual
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3.3.4
Timer/Counter Frequency and Interrupt ...................... 20
3.4
Interrupt Function............................................................ 21
3.4.1
Introduction .................................................................. 21
3.4.2
IRQ Level .................................................................... 21
3.4.3
Interrupt Control Register (Base + 32) ........................ 21
Table 3.2:Interrupt control register bit map ................. 21
3.4.4
Interrupt Source Control .............................................. 22
Figure 3.3:Figure 3-3: Interrupt sources ...................... 22
Table 3.3:Interrupt mode bit values ............................. 22
3.4.5
Interrupt Triggering Edge Control ............................... 23
Table 3.4:Triggering edge control bit values ............... 23
3.4.6
Interrupt Flag Bit ......................................................... 23
Table 3.5:Interrupt flag bit values ................................ 23
Appendix A Counter Chip Function................................. 26
A.1
The Intel 8254 ................................................................. 26
A.2
Counter Read/Write and Control Registers..................... 26
A.3
Counter Operating Modes ............................................... 29
A.3.1 MODE 0 – Stop on Terminal Count ............................ 29
A.3.2 MODE 1 – Programmable One-shot ........................... 29
A.3.3 MODE 2 – Rate Generator .......................................... 29
A.3.4 MODE 3 – Square Wave Generator ............................ 30
A.3.5 MODE 4 – Software Triggered Strobe ........................ 30
A.3.6 MODE 5 – Hardware Triggered Strobe ....................... 30
A.4
Counter Operations ......................................................... 31
A.4.1 Read/Write Operation .................................................. 31
A.4.2 Counter Read-back Command ..................................... 31
A.4.3 Counter Latch Operation ............................................. 31
A.5
Counter Applications....................................................... 32
Appendix B Register Format ............................................ 34
Summary of Contents for PCI-1751U
Page 1: ...PCI 1751U 48 bit Digital Input Output Card with Universal PCI Bus User Manual ...
Page 5: ...2 CHAPTER 1 General Information ...
Page 9: ...2 CHAPTER 2 Installation ...
Page 15: ...11 Chapter2 2 5 PCI 1751U Block Diagram Figure 2 2 PCI 1751U Block Diagram ...
Page 18: ...PCI 1751U User Manual 14 ...
Page 19: ...2 CHAPTER 3 Operation ...
Page 28: ...PCI 1751U User Manual 24 ...
Page 29: ...2 APPENDIX A Function of 8254 Counter Chip ...