Table of Contents
1.Introduction_________________________________________________________ 4
1.1General Description ___________________________________________________ 4
1.2Features _____________________________________________________________ 4
1.3Specifications _________________________________________________________ 5
1.3.1Power Consumption _________________________________________________________ 5
1.3.2Analog Inputs ______________________________________________________________ 5
1.3.3A/D Converter _____________________________________________________________ 5
1.3.4DA Converter ______________________________________________________________ 6
1.3.5Digital I/O_________________________________________________________________ 6
1.3.6Interrupt Channel ___________________________________________________________ 6
1.3.7Programmable Timer/Counter _________________________________________________ 7
1.3.8Applications _______________________________________________________________ 7
1.4Product Check List ____________________________________________________ 7
2.Hardware Configuration ______________________________________________ 8
2.1Board Layout_________________________________________________________ 8
2.2I/O Base Address Setting _______________________________________________ 9
2.3Jumper Setting ______________________________________________________ 10
2.3.1JP1 : D/A Internal Reference Voltage Selection_____________________________________ 10
2.4I/O Register Address__________________________________________________ 11
2.4.1The 8254 Counter __________________________________________________________ 12
2.4.2A/D Input Buffer Register ___________________________________________________ 12
2.4.3D/A Output Latch Register ___________________________________________________ 13
2.4.4D/I Input Buffer Register ____________________________________________________ 13
2.4.5Clear Interrupt Request______________________________________________________ 14
2.4.6A/D Gain Control Register ___________________________________________________ 14
2.4.7A/D Multiplex Control Register _______________________________________________ 15
2.4.8A/D Mode Control Register __________________________________________________ 16
2.4.9A/D Software Trigger Control Register _________________________________________ 17
2.4.10D/O Output Latch Register __________________________________________________ 18
2.5Digital I/O __________________________________________________________ 19
2.68254 Timer/Counter __________________________________________________ 20
2.7A/D Conversion ______________________________________________________ 21
2.7.1A/D conversion flow__________________________________________________________ 22
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