LM3S300 Luminary Micro, Inc, LM3S300 Datasheet - Page 98

• Manufacturer Part Number: LM3S300
• Description: Lm3s300 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
System Control
Deep Sleep Mode Clock Gating Control Register 2 (DCGC2)
Base 0x400F.E000
Offset 0x128
Type R/W, reset 0x00000000
98
Bit/Field
31:5
RO
RO
4
3
2
1
31
15
0
0
RO
RO
Register 27: Deep Sleep Mode Clock Gating Control Register 2 (DCGC2),
offset 0x128
This register controls the clock gating logic. Each bit controls a clock enable for a given interface,
function, or unit. If set, the unit receives a clock and functions. Otherwise, the unit is unclocked and
disabled (saving power). If the unit is unclocked, reads or writes to the unit will generate a bus fault.
The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional units are
disabled. It is the responsibility of software to enable the ports necessary for the application. Note
that these registers may contain more bits than there are interfaces, functions, or units to control.
This is to assure reasonable code compatibility with other family and future parts. RCGC2 is the
clock configuration register for running operation, SCGC2 for Sleep operation, and DCGC2 for
Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register
specifies that the system uses sleep modes.
30
14
0
0
RO
RO
29
13
reserved
0
0
GPIOE
GPIOD
GPIOC
GPIOB
Name
RO
RO
28
12
0
0
RO
RO
27
11
0
0
Type
R/W
R/W
R/W
R/W
RO
reserved
RO
RO
26
10
0
0
RO
RO
Reset
25
0
9
0
0
0
0
0
0
Preliminary
RO
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.
Port E Clock Gating Control
This bit controls the clock gating for Port E. If set, the unit receives a
clock and functions. Otherwise, the unit is unclocked and disabled. If
the unit is unclocked, reads or writes to the unit will generate a bus fault.
Port D Clock Gating Control
This bit controls the clock gating for Port D. If set, the unit receives a
clock and functions. Otherwise, the unit is unclocked and disabled. If
the unit is unclocked, reads or writes to the unit will generate a bus fault.
Port C Clock Gating Control
This bit controls the clock gating for Port C. If set, the unit receives a
clock and functions. Otherwise, the unit is unclocked and disabled. If
the unit is unclocked, reads or writes to the unit will generate a bus fault.
Port B Clock Gating Control
This bit controls the clock gating for Port B. If set, the unit receives a
clock and functions. Otherwise, the unit is unclocked and disabled. If
the unit is unclocked, reads or writes to the unit will generate a bus fault.
RO
RO
23
0
7
0
RO
RO
22
0
6
0
RO
RO
21
0
5
0
GPIOE
R/W
RO
20
0
4
0
GPIOD
R/W
RO
19
0
3
0
GPIOC
R/W
RO
18
0
2
0
GPIOB
R/W
RO
17
0
1
0
June 04, 2008
GPIOA
R/W
RO
16
0
0
0