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Contents
3.2 I/O Address Map................................................................14
3.3 Digital Data Registers.......................................................15
3.4 Control Register...............................................................15
3.5 External Trigger Enable Register......................................17
3.6 External Trigger Disable Register.....................................17
3.7 Change of State (COS) Control Register...........................17
3.8 Interrupt Source Control (ISC) Register.............................18
3.9 Clear Interrupt Register....................................................18
3.10 Timer/Counter Register.....................................................19
3.11 High Level Programming..................................................19
Chapter 4 Operation Theorem................................20
4.1 Digital I/O Ports.................................................................20
4.1.1 Introduction.....................................................................................20
4.1.2 External Trigger.............................................................................20
4.2 8254 Timer/Counter Operation..........................................21
4.2.1 Introduction.....................................................................................21
4.2.2 Cascaded 32 bits Timer..............................................................22
4.2.3 Event Counter and Edge Control..............................................22
4.3 Interrupt Circuit.................................................................22
4.3.1 System Architecture....................................................................22
4.3.2 IRQ Level Setting...........................................................................22
4.3.3 Dual Interrupt System..................................................................22
4.3.4 Interrupt Source Control (ISC)...................................................23
4.3.5 Change of State (COS) Interrupt...............................................24
4.4 12V and 5V Power Supply................................................25
Chapter 5 C/C++ Libraries.......................................26
5.1 Libraries Installation........................................................26
5.2 Programming Guide .........................................................27
5.2.1 Naming Convention......................................................................27
5.2.2 Data Types......................................................................................27
5.3 _7396_Initial......................................................................28
5.4 _7396_DI............................................................................28
5.5 _7396_DO..........................................................................30
5.6 _7396_Config_Port ............................................................30
5.7 _7396_Software_Reset......................................................33
5.8 _7396_INT_Source_Control ...............................................33
5.9 _7396_COSIRQ_Control.....................................................34
