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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
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
CONTENTS
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