LM3S3749 Luminary Micro, Inc, LM3S3749 Datasheet - Page 662

• Manufacturer Part Number: LM3S3749
• Description: Lm3s3749 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
Quadrature Encoder Interface (QEI)
QEI Control (QEICTL)
QEI0 base: 0x4002.C000
Offset 0x000
Type R/W, reset 0x0000.0000
662
Bit/Field
31:13
8:6
12
11
10
RO
RO
9
31
15
0
0
reserved
RO
RO
Register 1: QEI Control (QEICTL), offset 0x000
This register contains the configuration of the QEI module. Separate enables are provided for the
quadrature encoder and the velocity capture blocks; the quadrature encoder must be enabled in
order to capture the velocity, but the velocity does not need to be captured in applications that do
not need it. The phase signal interpretation, phase swap, Position Update mode, Position Reset
mode, and velocity predivider are all set via this register.
30
14
0
0
RO
RO
STALLEN
29
13
reserved
0
0
VelDiv
Name
INVB
INVA
INVI
STALLEN
R/W
RO
28
12
0
0
INVI
R/W
RO
27
11
0
0
Type
R/W
R/W
R/W
R/W
R/W
RO
INVB
R/W
RO
26
10
0
0
INVA
R/W
RO
Reset
25
0x00
0
9
0
0x0
0
0
0
0
Preliminary
R/W
RO
24
0
8
0
reserved
Description
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Stall QEI
When set, the QEI stalls when the microcontroller asserts Halt.
Invert Index Pulse
When set , the input Index Pulse is inverted.
Invert PhB
When set, the PhB input is inverted.
Invert PhA
When set, the PhA input is inverted.
Predivide Velocity
A predivider of the input quadrature pulses before being applied to the
QEICOUNT accumulator. This field can be set to the following values:
Value
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
VelDiv
R/W
RO
23
0
7
0
Predivider
÷128
÷16
÷32
÷64
÷1
÷2
÷4
÷8
R/W
RO
22
0
6
0
VelEn
R/W
RO
21
0
5
0
ResMode
R/W
RO
20
0
4
0
CapMode
R/W
RO
19
0
3
0
SigMode
R/W
RO
18
0
2
0
Swap
R/W
RO
17
0
1
0
June 02, 2008
Enable
R/W
RO
16
0
0
0