LM3S1138 Luminary Micro, Inc, LM3S1138 Datasheet - Page 420

• Manufacturer Part Number: LM3S1138
• Description: Lm3s1138 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
Analog Comparators
Analog Comparator Reference Voltage Control (ACREFCTL)
Base 0x4003.C000
Offset 0x10
Type R/W, reset 0x0000.0000
420
Bit/Field
31:10
7:4
3:0
9
8
RO
RO
31
15
0
0
Register 4: Analog Comparator Reference Voltage Control (ACREFCTL), offset
0x10
This register specifies whether the resistor ladder is powered on as well as the range and tap.
RO
RO
30
14
0
0
reserved
reserved
RO
RO
29
13
0
0
Name
VREF
RNG
reserved
EN
RO
RO
28
12
0
0
RO
RO
27
11
0
0
Type
R/W
R/W
R/W
RO
RO
RO
RO
26
10
0
0
Reset
0x00
0x00
0x00
R/W
RO
EN
25
0
9
0
0
0
Preliminary
RNG
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.
Resistor Ladder Enable
The EN bit specifies whether the resistor ladder is powered on. If 0, the
resistor ladder is unpowered. If 1, the resistor ladder is connected to
the analog V
This bit is reset to 0 so that the internal reference consumes the least
amount of power if not used and programmed.
Resistor Ladder Range
The RNG bit specifies the range of the resistor ladder. If 0, the resistor
ladder has a total resistance of 31 R. If 1, the resistor ladder has a total
resistance of 23 R.
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.
Resistor Ladder Voltage Ref
The VREF bit field specifies the resistor ladder tap that is passed through
an analog multiplexer. The voltage corresponding to the tap position is
the internal reference voltage available for comparison. See Table
16-4 on page 414 for some output reference voltage examples.
reserved
RO
RO
23
0
7
0
DD
.
RO
RO
22
0
6
0
reserved
RO
RO
21
0
5
0
RO
RO
20
0
4
0
R/W
RO
19
0
3
0
R/W
RO
18
0
2
0
VREF
July 26, 2008
R/W
RO
17
0
1
0
R/W
RO
16
0
0
0