Datasheet

© 2009-2012 Microchip Technology Inc. Preliminary DS70616F-page 319
dsPIC33EPXXX(GP/MC/MU)806/810/814 and PIC24EPXXX(GP/GU)810/814
17.0 QUADRATURE ENCODER
INTERFACE (QEI) MODULE
(dsPIC33EPXXX(MC/MU)8XX
DEVICES ONLY)
This chapter describes the Quadrature Encoder Inter-
face (QEI) module and associated operational modes.
The QEI module provides the interface to incremental
encoders for obtaining mechanical position data.
The operational features of the QEI module include:
• 32-bit position counter
• 32-bit Index pulse counter
• 32-bit Interval timer
• 16-bit velocity counter
• 32-bit Position Initialization/Capture/Compare
High register
• 32-bit Position Compare Low register
• x4 Quadrature Count mode
• External Up/Down Count mode
• External Gated Count mode
• External Gated Timer mode
• Internal Timer mode
Figure 17-1 illustrates the QEI block diagram.
Note 1: This data sheet summarizes the features
of the dsPIC33EPXXX(GP/MC/MU)806/
810/814 and PIC24EPXXX(GP/GU)810/
814 families of devices. It is not intended
to be a comprehensive reference source.
To complement the information in this
data sheet, refer to Section 15.
“Quadrature Encoder Interface (QEI)”
(DS70601) of the “dsPIC33E/PIC24E
Family Reference Manual”, which is
available from the Microchip web site
(www.microchip.com).
2: Some registers and associated bits
described in this section may not be
available on all devices. Refer to
Section 4.0 “Memory Organization” in
this data sheet for device-specific register
and bit information.
Note: An ‘x’ used in the names of pins, control/
status bits and registers denotes a
particular Quadrature Encoder Interface
(QEI) module number (x = 1 or 2).