DSPIC30F2010 MICROCHIP [Microchip Technology], DSPIC30F2010 Datasheet - Page 77

• Manufacturer Part Number: DSPIC30F2010
• Description: High-Performance, 16-Bit Digital Signal Controllers
• Manufacturer: MICROCHIP [Microchip Technology]

13.0
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 motor positioning data. Incre-
mental encoders are very useful in motor control
applications.
FIGURE 13-1:
© 2006 Microchip Technology Inc.
Note: This data sheet summarizes features of this group
of dsPIC30F devices and is not intended to be a complete
reference source. For more information on the CPU,
peripherals, register descriptions and general device
functionality, refer to the “dsPIC30F Family Reference
Manual” (DS70046).
INDX
QEA
QEB
QUADRATURE ENCODER
INTERFACE (QEI) MODULE
Synchronize
Sleep Input
Det
QUADRATURE ENCODER INTERFACE BLOCK DIAGRAM
UPDN_SRC
Programmable
Programmable
Programmable
1
0
Digital Filter
Digital Filter
Digital Filter
QEICON<11>
3
T
QEIM<2:0>
CY
Quadrature
Encoder
Interface Logic
TQCS
1
0
QEIM<2:0>
Mode Select
3
TQGATE
1
0
2
The Quadrature Encoder Interface (QEI) is a key fea-
ture requirement for several motor control applications,
such as Switched Reluctance (SR) and AC Induction
Motor (ACIM). The operational features of the QEI are,
but not limited to:
• Three input channels for two phase signals and
• 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
Figure 13-1 depicts the Quadrature Encoder Interface
block diagram.
index pulse
16-bit Up/Down Counter
Max Count Register
D
CK
Comparator/
Zero Detect
(POSCNT)
(MAXCNT)
TQCKPS<1:0>
Q
Q
1, 8, 64, 256
Prescaler
bits
2
dsPIC30F2010
QEIM<2:0>
Reset
Equal
(QEICON<10:8>).
DS70118G-page 75
QEIIF
Event
Flag