Digital I/O Registers
697
SLAU356I – March 2015 – Revised June 2019
Copyright © 2015–2019, Texas Instruments Incorporated
Digital I/O
12.4.5 PxREN Register
Port X Pullup or Pulldown Resistor Enable Register (X = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or J)
Figure 12-5. PxREN Register
7
6
5
4
3
2
1
0
PxREN
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
Table 12-8. PxREN Register Description
Bit
Field
Type
Reset
Description
7-0
PxREN
RW
0h
Port X pullup or pulldown resistor enable. When the port is configured as an
input, setting this bit enables or disables the pullup or pulldown.
0b = Pullup or pulldown disabled
1b = Pullup or pulldown enabled
12.4.6 PxDS Register
Port X Drive Strength Selection Register (X = 1, 2, 3, 4, 5, 6, 7, 8, 9 ,10 or J)
Figure 12-6. PxDS Register
7
6
5
4
3
2
1
0
PxDS
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
Table 12-9. PxDS Register Description
Bit
Field
Type
Reset
Description
7-0
PxDS
RW
0h
Port X drive strength selection (for high drive strength I/Os).
0b = High drive strength I/Os configured for regular drive strength.
1b = High drive strength I/Os configured for high drive strength.
If high drive strength is not implemented specific I/Os the corresponding bits in
this register will always read 0.
12.4.7 PxSEL0 Register
Port X Function Selection Register 0 (X = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or J)
Figure 12-7. PxSEL0 Register
7
6
5
4
3
2
1
0
PxSEL0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
Table 12-10. PxSEL0 Register Description
Bit
Field
Type
Reset
Description
7-0
PxSEL0
RW
0h
Port function selection. Each bit corresponds to one channel on Port X.
The values of each bit position in PxSEL1 and PxSEL0 are combined to specify
the function. For example, if P1SEL1.5 = 1 and P1SEL0.5 = 0, then the
secondary module function is selected for P1.5.
See PxSEL1 for the definition of each value.