LM3S308 Luminary Micro, Inc, LM3S308 Datasheet - Page 134

• Manufacturer Part Number: LM3S308
• Description: Lm3s308 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
General-Purpose Input/Outputs (GPIOs)
GPIO Direction (GPIODIR)
GPIO Port A base: 0x4000.4000
GPIO Port B base: 0x4000.5000
GPIO Port C base: 0x4000.6000
GPIO Port D base: 0x4000.7000
GPIO Port E base: 0x4002.4000
Offset 0x400
Type R/W, reset 0x0000.0000
134
Bit/Field
31:8
7:0
RO
RO
31
15
0
0
RO
RO
Register 2: GPIO Direction (GPIODIR), offset 0x400
The GPIODIR register is the data direction register. Bits set to 1 in the GPIODIR register configure
the corresponding pin to be an output, while bits set to 0 configure the pins to be inputs. All bits are
cleared by a reset, meaning all GPIO pins are inputs by default.
30
14
0
0
RO
RO
29
13
reserved
0
0
Name
DIR
RO
RO
28
12
0
0
reserved
RO
RO
27
11
0
0
Type
R/W
RO
RO
RO
26
10
0
0
RO
RO
Reset
25
0x00
0x00
0
9
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.
GPIO Data Direction
The DIR values are defined as follows:
Value
0
1
R/W
RO
23
0
7
0
Description
Pins are inputs.
Pins are outputs.
R/W
RO
22
0
6
0
R/W
RO
21
0
5
0
R/W
RO
20
0
4
0
DIR
R/W
RO
19
0
3
0
R/W
RO
18
0
2
0
R/W
RO
17
0
1
0
June 04, 2008
R/W
RO
16
0
0
0