LM3S1911-IQC20-A0 ETC2 [List of Unclassifed Manufacturers], LM3S1911-IQC20-A0 Datasheet - Page 153

• Manufacturer Part Number: LM3S1911-IQC20-A0
• Description: Microcontroller
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

9
9.1
9.1.1
9.1.1.1
October 09, 2007
General-Purpose Input/Outputs (GPIOs)
The GPIO module is composed of eight physical GPIO blocks, each corresponding to an individual
GPIO port (Port A, Port B, Port C, Port D, Port E, Port F, Port G, and Port H). The GPIO module is
FiRM-compliant and supports 23-60 programmable input/output pins, depending on the peripherals
being used.
The GPIO module has the following features:
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Functional Description
Important:
Each GPIO port is a separate hardware instantiation of the same physical block. The LM3S1911
microcontroller contains eight ports and thus eight of these physical GPIO blocks.
Data Control
The data control registers allow software to configure the operational modes of the GPIOs. The data
direction register configures the GPIO as an input or an output while the data register either captures
incoming data or drives it out to the pads.
Data Direction Operation
The GPIO Direction (GPIODIR) register (see page 160) is used to configure each individual pin as
an input or output. When the data direction bit is set to 0, the GPIO is configured as an input and
the corresponding data register bit will capture and store the value on the GPIO port. When the data
Programmable control for GPIO interrupts
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5-V-tolerant input/outputs
Bit masking in both read and write operations through address lines
Programmable control for GPIO pad configuration
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Interrupt generation masking
Edge-triggered on rising, falling, or both
Level-sensitive on High or Low values
Weak pull-up or pull-down resistors
2-mA, 4-mA, and 8-mA pad drive
Slew rate control for the 8-mA drive
Open drain enables
Digital input enables
All GPIO pins are tri-stated by default (GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0,
and GPIOPUR=0), with the exception of the five JTAG/SWD pins (PB7 and PC[3:0]).
The JTAG/SWD pins default to their JTAG/SWD functionality (GPIOAFSEL=1,
GPIODEN=1 and GPIOPUR=1). A Power-On-Reset (POR) or asserting RST puts both
groups of pins back to their default state.
Preliminary
LM3S1911 Microcontroller
153