LM3S8971 Luminary Micro, Inc, LM3S8971 Datasheet - Page 503

• Manufacturer Part Number: LM3S8971
• Description: Lm3s8971 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
PWM0 Generator A Control (PWM0GENA)
Base 0x4002.8000
Offset 0x060
Type R/W, reset 0x0000.0000
July 26, 2008
Bit/Field
31:12
11:10
RO
RO
31
15
0
0
Register 34: PWM0 Generator A Control (PWM0GENA), offset 0x060
Register 35: PWM1 Generator A Control (PWM1GENA), offset 0x0A0
Register 36: PWM2 Generator A Control (PWM2GENA), offset 0x0E0
These registers control the generation of the PWMnA signal based on the load and zero output pulses
from the counter, as well as the compare A and compare B pulses from the comparators
(PWM0GENA controls the PWM generator 0 block, and so on). When the counter is running in
Count-Down mode, only four of these events occur; when running in Count-Up/Down mode, all six
occur. These events provide great flexibility in the positioning and duty cycle of the PWM signal that
is produced.
The PWM0GENA register controls generation of the PWM0A signal; PWM1GENA, the PWM1A signal;
and PWM2GENA, the PWM2A signal.
If a zero or load event coincides with a compare A or compare B event, the zero or load action is
taken and the compare A or compare B action is ignored. If a compare A event coincides with a
compare B event, the compare A action is taken and the compare B action is ignored.
RO
RO
30
14
0
0
reserved
ActCmpBD
reserved
RO
RO
29
13
0
0
Name
RO
RO
28
12
0
0
R/W
RO
27
11
0
0
ActCmpBD
Type
R/W
RO
R/W
RO
26
10
0
0
Reset
0x00
R/W
0x0
RO
25
0
9
0
ActCmpBU
Preliminary
R/W
RO
24
0
8
0
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.
Action for Comparator B Down
The action to be taken when the counter matches comparator B while
counting down.
The table below defines the effect of the event on the output signal.
Value
reserved
0x0
0x1
0x2
0x3
R/W
RO
23
Description
Do nothing.
Invert the output signal.
Set the output signal to 0.
Set the output signal to 1.
0
7
0
ActCmpAD
R/W
RO
22
0
6
0
R/W
RO
21
0
5
0
ActCmpAU
R/W
RO
20
0
4
0
LM3S8971 Microcontroller
R/W
RO
19
0
3
0
ActLoad
R/W
RO
18
0
2
0
R/W
RO
17
0
1
0
ActZero
R/W
RO
16
0
0
0
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