LM3S611-IQN50-C2T Datasheet, PDF (236/574 Pages) Texas Instruments – Stellaris® LM3S611 Microcontroller

NRND: Not recommended for new designs.
General-Purpose Input/Outputs (GPIOs)
Table 7-5. GPIO Interrupt Configuration Example (continued)
Desired
Pin 2 Bit Value^a
Register
Interrupt
Event
7
6
5
4
3
Trigger
GPIOIEV 0=Low level,
X
X
X
X
X
or negative
edge
1=High level,
or positive
edge
GPIOIM
0=masked
0
0
0
0
0
1=not
masked
a. X=Ignored (don’t care bit)
2
1
1
1
X
0
0
X
0
7.5 Register Map
Table 7-6 on page 236 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 203). 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
R/W
0x400 GPIODIR
R/W
0x404 GPIOIS
R/W
0x408 GPIOIBE
R/W
0x40C GPIOIEV
R/W
0x410 GPIOIM
R/W
Reset
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
0x0000.0000
Description
GPIO Data
GPIO Direction
GPIO Interrupt Sense
GPIO Interrupt Both Edges
GPIO Interrupt Event
GPIO Interrupt Mask
See
page
238
239
240
241
242
243
236
June 18, 2012
Texas Instruments-Production Data