LM3S101 Datasheet, PDF (381/445 Pages) List of Unclassifed Manufacturers – Microcontroller

Stellaris^® LM3S101 Microcontroller
Figure 12-2. Structure of Comparator Unit
-ve input
+ve input ⁰
1
+ve input (alternate)
2
reference input
CINV
output
IntGen
ACCTL
ACSTAT
A comparator is configured through two status/control registers (ACCTL and ACSTAT ). The internal
reference is configured through one control register (ACREFCTL). Interrupt status and control is
configured through three registers (ACMIS, ACRIS, and ACINTEN). The operating modes of the
comparators are shown in the Comparator Operating Mode tables.
Typically, the comparator output is used internally to generate controller interrupts. It may also be
used to drive an external pin.
Important: The ASRCP bits in the ACCTLn register must be set before using the analog
comparators. The proper pad configuration for the comparator input and output pins
are described in the Comparator Operating Mode tables.
Table 12-3. Comparator 0 Operating Modes
ACCTL0
Comparator 0
ASRCP
00
VIN-
C0-
VIN+
C0+
Output
C0o/C1-^a
01
C0-
C0+
C0o/C1-
10
C0-
Vref
C0o/C1-
11
C0-
reserved
C0o/C1-
a. C0o and C1- signals share a single pin and may only be used as one or the other.
Table 12-4. Comparator 1 Operating Modes
ACCTL1
Comparator 1
ASRCP
00
VIN-
C0o/C1-^a
VIN+
n/a
Output
n/a
01
C0o/C1-
C0+
n/a
10
C0o/C1-
Vref
n/a
11
C0o/C1-
reserved
n/a
a. C0o and C1- signals share a single pin and may only be used as one or the other.
Interrupt
yes
yes
yes
yes
Interrupt
yes
yes
yes
yes
July 14, 2014
381
Texas Instruments-Production Data