Microchip Technology DM330023-2 Data Sheet
© 2007-2012 Microchip Technology Inc.
DS70283K-page 173
dsPIC33FJ32MC202/204 and dsPIC33FJ16MC304
16.0 QUADRATURE ENCODER
INTERFACE (QEI) MODULE
This section 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 include:
• Three input channels for two phase signals and
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 include:
• Three input channels for two phase signals and
index pulse
• 16-bit up/down position counter
• Count direction status
• Position Measurement (x2 and x4) mode
• Programmable digital noise filters on inputs
• Alternate 16-bit Timer/Counter mode
• Quadrature Encoder Interface interrupts
These operating modes are determined by setting the
appropriate bits, QEIM<2:0> in (QEIxCON<10:8>).
• Count direction status
• Position Measurement (x2 and x4) mode
• Programmable digital noise filters on inputs
• Alternate 16-bit Timer/Counter mode
• Quadrature Encoder Interface interrupts
These operating modes are determined by setting the
appropriate bits, QEIM<2:0> in (QEIxCON<10:8>).
depicts the Quadrature Encoder Interface
block diagram.
FIGURE 16-1:
QUADRATURE ENCODER INTERFACE BLOCK DIAGRAM
Note 1: This data sheet summarizes the features
of the dsPIC33FJ32MC202/204 and
dsPIC33FJ16MC304 family 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)” (DS70208) of the
“dsPIC33F/PIC24H Family Reference
Manual”, which is available from the
Microchip website (
dsPIC33FJ16MC304 family 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)” (DS70208) of the
“dsPIC33F/PIC24H Family Reference
Manual”, which is available from the
Microchip website (
www.microchip.com
).
2: Some registers and associated bits
described in this section may not be
available on all devices. Refer to
available on all devices. Refer to
in
this data sheet for device-specific register
and bit information.
and bit information.
16-bit Up/Down Counter
Comparator/
Max Count Register
QEAx
INDXx
0
1
Up/Down
Existing Pin Logic
UPDNx
3
QEBx
QEIM<2:0>
Mode Select
3
(POSCNT)
(MAXCNT)
PCDOUT
QEIIF
Event
Flag
Event
Flag
Reset
Equal
2
T
CY
1
0
TQCS
TQCKPS<1:0>
2
Q
Q
D
CK
TQGATE
QEIM<2:0>
1
0
Sleep Input
0
1
UPDN_SRC
QEIxCON<11>
Zero Detect
Synchronize
Det
1, 8, 64, 256
Prescaler
Quadrature
Encoder
Interface Logic
Programmable
Digital Filter
Programmable
Digital Filter
Programmable
Digital Filter