LM3S812_16 Datasheet, PDF (232/590 Pages) Texas Instruments – Stellaris LM3S812 Microcontroller

General-Purpose Input/Outputs (GPIOs)
(GPIOPCTL) register to the numeric enoding shown in the table below. Note that each pin must be
programmed individually; no type of grouping is implied by the columns in the table.
Important: All GPIO pins are configured as GPIOs and tri-stated by default (GPIOAFSEL=0,
GPIODEN=0, GPIOPDR=0, GPIOPUR=0, and GPIOPCTL=0, with the exception of the
four JTAG/SWD pins (shown in the table below). A Power-On-Reset (POR) or asserting
RST puts the pins back to their default state.
Table 7-1. GPIO Pins With Non-Zero Reset Values
GPIO Pins
PA[1:0]
PA[5:2]
PB[3:2]
PC[3:0]
Default State
UART0
SSI0
I²C0
JTAG/SWD
GPIOAFSEL GPIODEN GPIOPDR GPIOPUR
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
GPIOPCTL
0x1
0x1
0x1
0x3
Table 7-2. GPIO Pins and Alternate Functions (48QFP)
IO
Pin Number
Multiplexed Function
PA0
17
U0Rx
PA1
18
U0Tx
PA2
19
SSIClk
PA3
20
SSIFss
PA4
21
SSIRx
PA5
22
SSITx
PB0
29
CCP0
PB1
30
PB2
33
I2CSCL
PB3
34
I2CSDA
PB4
44
C0-
PB5
43
CCP5
PB6
42
C0+
PB7
41
TRST
PC0
40
TCK
PC1
39
TMS
PC2
38
TDI
PC3
37
TDO
PC4
14
PC5
13
PC6
12
CCP3
PC7
11
CCP4
PD0
25
PWM0
PD1
26
PWM1
PD2
27
U1Rx
PD3
28
U1Tx
PD4
45
Multiplexed Function
SWCLK
SWDIO
SWO
232
July 14, 2014
Texas Instruments-Production Data