Datasheet

 2011-2013 Microchip Technology Inc. DS70657G-page 247
dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X AND PIC24EPXXXGP/MC20X
17.0 QUADRATURE ENCODER
INTERFACE (QEI) MODULE
(dsPIC33EPXXXMC20X/50X
and PIC24EPXXXMC20X
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 dsPIC33EPXXXGP50X,
dsPIC33EPXXXMC20X/50X and
PIC24EPXXXGP/MC20X families of
devices. It is not intended to be a
comprehensive reference source. To com-
plement 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.