LM3S2139 Luminary Micro, Inc, LM3S2139 Datasheet - Page 158

• Manufacturer Part Number: LM3S2139
• Description: Lm3s2139 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

General-Purpose Input/Outputs (GPIOs)
158
Bit/Field
7:0
AFSEL
Name
Type
R/W
Reset
-
Preliminary
Description
GPIO Alternate Function Select
The AFSEL values are defined as follows:
Value
0
1
Description
Software control of corresponding GPIO line (GPIO mode).
Hardware control of corresponding GPIO line (alternate
hardware function).
Note:
The default reset value for the GPIOAFSEL,
GPIOPUR, and GPIODEN registers are 0x0000.0000
for all GPIO pins, with the exception of the five
JTAG/SWD pins (PB7 and PC[3:0]). These five pins
default to JTAG/SWD functionality. Because of this,
the default reset value of these registers for GPIO
Port B is 0x0000.0080 while the default reset value
for Port C is 0x0000.000F.
July 25, 2008