Intel 8XC196NT, User Manual

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CONTENTS
10.3.2 Quadrature Clocking Mode .....................................................................................10-7
10.4 EPA CHANNEL FUNCTIONAL OVERVIEW ............................................................... 10-9
10.4.1 Operating in Capture Mode ...................................................................................10-11
10.4.1.1 Handling EPA Overruns ...................................................................................10-12
10.4.2 Operating in Compare Mode .................................................................................10-13
10.4.2.1 Generating a Low-speed PWM Output ............................................................10-14
10.4.2.2 Generating a Medium-speed PWM Output ......................................................10-15
10.4.2.3 Generating a High-speed PWM Output ...........................................................10-16
10.4.2.4 Generating the Highest-speed PWM Output ....................................................10-16
10.5 PROGRAMMING THE EPA AND TIMER/COUNTERS............................................. 10-17
10.5.1 Configuring the EPA and Timer/Counter Port Pins ...............................................10-17
10.5.2 Programming the Timers .......................................................................................10-17
10.5.3 Programming the Capture/Compare Channels .....................................................10-20
10.5.4 Programming the Compare-only Channels ...........................................................10-25
10.6 ENABLING THE EPA INTERRUPTS ........................................................................ 10-26
10.7 DETERMINING EVENT STATUS.............................................................................. 10-27
10.8 SERVICING THE MULTIPLEXED EPA INTERRUPT WITH SOFTWARE................ 10-29
10.8.1 Using the TIJMP Instruction to Reduce Interrupt Service Overhead ....................10-31
10.9 PROGRAMMING EXAMPLES FOR EPA CHANNELS ............................................. 10-33
10.9.1 EPA Compare Event Program ..............................................................................10-33
10.9.2 EPA Capture Event Program ................................................................................10-34
10.9.3 EPA PWM Output Program ..................................................................................10-35
CHAPTER 11
ANALOG-TO-DIGITAL CONVERTER
11.1 A/D CONVERTER FUNCTIONAL OVERVIEW ........................................................... 11-1
11.2 A/D CONVERTER SIGNALS AND REGISTERS ........................................................ 11-2
11.3 A/D CONVERTER OPERATION ................................................................................. 11-3
11.4 PROGRAMMING THE A/D CONVERTER .................................................................. 11-4
11.4.1 Programming the A/D Test Register .......................................................................11-5
11.4.2 Programming the A/D Result Register (for Threshold Detection Only) ...................11-6
11.4.3 Programming the A/D Time Register ......................................................................11-6
11.4.4 Programming the A/D Command Register ..............................................................11-8
11.4.5 Enabling the A/D Interrupt .......................................................................................11-9
11.5 DETERMINING A/D STATUS AND CONVERSION RESULTS .................................. 11-9
11.6 DESIGN CONSIDERATIONS.................................................................................... 11-10
11.6.1 Designing External Interface Circuitry ...................................................................11-11
11.6.1.1 Minimizing the Effect of High Input Source Resistance ....................................11-12
11.6.1.2 Suggested A/D Input Circuit .............................................................................11-13
11.6.1.3 Analog Ground and Reference Voltages .........................................................11-13
11.6.1.4 Using Mixed Analog and Digital Inputs ............................................................11-14
11.6.2 Understanding A/D Conversion Errors ..................................................................11-14