LM3S310 Datasheet, PDF (232/506 Pages) List of Unclassifed Manufacturers – Microcontroller

General-Purpose Input/Outputs (GPIOs)
7.5 Register Map
Table 7-6 on page 232 lists the GPIO registers. The offset listed is a hexadecimal increment to the
register’s address, relative to that GPIO port’s base address:
■ GPIO Port A: 0x4000.4000
■ GPIO Port B: 0x4000.5000
■ GPIO Port C: 0x4000.6000
■ GPIO Port D: 0x4000.7000
■ GPIO Port E: 0x4002.4000
Note that the GPIO module clock must be enabled before the registers can be programmed (see
page 197). There must be a delay of 3 system clocks after the GPIO module clock is enabled before
any GPIO module registers are accessed.
Important: The GPIO registers in this chapter are duplicated in each GPIO block; however,
depending on the block, all eight bits may not be connected to a GPIO pad. In those
cases, writing to those unconnected bits has no effect, and reading those unconnected
bits returns no meaningful data.
Note:
The default reset value for the GPIOAFSEL register is 0x0000.0000 for all GPIO pins, with
the exception of the five JTAG pins (PB7 and PC[3:0]). These five pins default to JTAG
functionality. Because of this, the default reset value of GPIOAFSEL for GPIO Port B is
0x0000.0080 while the default reset value for Port C is 0x0000.000F.
Table 7-6. GPIO Register Map
Offset Name
Type
0x000 GPIODATA
0x400 GPIODIR
0x404 GPIOIS
0x408 GPIOIBE
0x40C GPIOIEV
0x410 GPIOIM
0x414 GPIORIS
0x418 GPIOMIS
0x41C GPIOICR
0x420 GPIOAFSEL
0x500 GPIODR2R
0x504 GPIODR4R
0x508 GPIODR8R
0x50C GPIOODR
0x510 GPIOPUR
0x514 GPIOPDR
R/W
R/W
R/W
R/W
R/W
R/W
RO
RO
W1C
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
-
0x0000.00FF
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.00FF
0x0000.0000
Description
GPIO Data
GPIO Direction
GPIO Interrupt Sense
GPIO Interrupt Both Edges
GPIO Interrupt Event
GPIO Interrupt Mask
GPIO Raw Interrupt Status
GPIO Masked Interrupt Status
GPIO Interrupt Clear
GPIO Alternate Function Select
GPIO 2-mA Drive Select
GPIO 4-mA Drive Select
GPIO 8-mA Drive Select
GPIO Open Drain Select
GPIO Pull-Up Select
GPIO Pull-Down Select
See
page
234
235
236
237
238
239
240
241
242
243
245
246
247
248
249
250
232
July 14, 2014
Texas Instruments-Production Data