LM3S608 Datasheet, PDF (124/416 Pages) List of Unclassifed Manufacturers – Microcontroller

General-Purpose Input/Outputs (GPIOs)
8 General-Purpose Input/Outputs (GPIOs)
The GPIO module is composed of five physical GPIO blocks, each corresponding to an individual
GPIO port (Port A, Port B, Port C, Port D, and Port E, ). The GPIO module is FiRM-compliant and
supports 5-28 programmable input/output pins, depending on the peripherals being used.
The GPIO module has the following features:
■ Programmable control for GPIO interrupts
– Interrupt generation masking
– Edge-triggered on rising, falling, or both
– Level-sensitive on High or Low values
■ 5-V-tolerant input/outputs
■ Bit masking in both read and write operations through address lines
■ Programmable control for GPIO pad configuration
– 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
8.1 Functional Description
Important: All GPIO pins are inputs by default (GPIODIR=0 and GPIOAFSEL=0), with the exception
of the five JTAG pins (PB7 and PC[3:0]). The JTAG pins default to their JTAG
functionality (GPIOAFSEL=1). A Power-On-Reset (POR) or asserting an external reset
(RST) puts both groups of pins back to their default state.
Each GPIO port is a separate hardware instantiation of the same physical block (see Figure
8-1 on page 125). The LM3S608 microcontroller contains five ports and thus five of these physical
GPIO blocks.
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October 01, 2007
Preliminary