LM3S1751_16 Datasheet, PDF (584/679 Pages) Texas Instruments – Stellaris LM3S1751 Microcontroller

Pulse Width Modulator (PWM)
Register 24: PWM0 Compare B (PWM0CMPB), offset 0x05C
Register 25: PWM1 Compare B (PWM1CMPB), offset 0x09C
These registers contain a value to be compared against the counter (PWM0CMPB controls the
PWM generator 0 block, and so on). When this value matches the counter, a pulse is output; this
can drive the generation of a PWM signal (via the PWMnGENA/PWMnGENB registers) or drive an
interrupt or ADC trigger (via the PWMnINTEN register). If the value of this register is greater than
the PWMnLOAD register, no pulse is ever output.
If the comparator B update mode is immediate (based on the CmpBUpd bit in the PWMnCTL register),
this 16-bit CompB value is used the next time the counter reaches zero. If the update mode is
synchronous, it is used the next time the counter reaches zero after a synchronous update has been
requested through the PWM Master Control (PWMCTL) register (see page 565). If this register is
rewritten before the actual update occurs, the previous value is never used and is lost.
PWM0 Compare B (PWM0CMPB)
Base 0x4002.8000
Offset 0x05C
Type R/W, reset 0x0000.0000
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
reserved
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
CompB
Type R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit/Field
31:16
15:0
Name
reserved
CompB
Type
RO
R/W
Reset
0x00
0x00
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.
Comparator B Value
The value to be compared against the counter.
584
July 15, 2014
Texas Instruments-Production Data