eQEP
C2000 Microcontroller Workshop - Control Peripherals
7 - 43
eQEP
What is an Incremental Quadrature
Encoder?
A digital (angular) position sensor
slots spaced
θ
deg. apart
photo sensors spaced
θ
/4 deg. apart
light source (LED)
shaft rotation
Ch. A
Ch. B
Quadrature Output from Photo Sensors
θ
θ
/4
Incremental Optical Encoder
The eQEP circuit, when enabled, decodes and counts the quadrature encoded input pulses. The
QEP circuit can be used to interface with an optical encoder to get position and speed information
from a rotating machine.
How is Position Determined from
Quadrature Signals?
Ch. A
Ch. B
(00) (11)
(10) (01)
(A,B) =
00
01
11
10
Quadrature Decoder
State Machine
increment
counter
decrement
counter
Position resolution is
θ
/4 degrees
Illegal
Transitions;
generate
phase error
interrupt
Содержание C2000 Piccolo LaunchPad
Страница 74: ...Interrupts 4 18 C2000 Microcontroller Workshop Reset and Interrupts ...
Страница 100: ...Lab 5 System Initialization 5 26 C2000 Microcontroller Workshop System Initialization ...
Страница 126: ...Lab 6 Analog to Digital Converter 6 26 C2000 Microcontroller Workshop Analog to Digital Converter ...
Страница 218: ...Lab 8 IQmath FIR Filter 8 42 C2000 Microcontroller Workshop Numerical Concepts ...
Страница 236: ...Lab 9 Servicing the ADC with DMA 9 18 C2000 Microcontroller Workshop Direct Memory Access Controller ...
Страница 260: ...Lab 10 CLA Floating Point FIR Filter 10 24 C2000 Microcontroller Workshop Control Law Accelerator ...
Страница 331: ...C2000 Microcontroller Workshop Appendix A Experimenter s Kit A 1 Appendix A Experimenter s Kit ...
Страница 334: ...F28069 controlCARD A 4 C2000 Microcontroller Workshop Appendix A Experimenter s Kit SW2 ...
Страница 336: ...F28035 controlCARD A 6 C2000 Microcontroller Workshop Appendix A Experimenter s Kit SW2 SW3 ...
Страница 338: ...F28335 controlCARD A 8 C2000 Microcontroller Workshop Appendix A Experimenter s Kit LD1 LD2 LD3 SW1 ...