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SYSCFG Registers
279
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
System Configuration (SYSCFG) Module
10.5.22 Pullup/Pulldown Enable Register (PUPD_ENA)
The pullup/pulldown enable register (PUPD_ENA) enables the pull-up or pull-down functionality for the pin
group
n
defined in your device-specific data manual. The PUPD_ENA is shown in
and
described in
Figure 10-49. Pullup/Pulldown Enable Register (PUPD_ENA)
31
0
PUPDENA[
n
]
R/W-FFFF FFFFh
LEGEND: R/W = Read/Write; -
n
= value after reset
Table 10-53. Pullup/Pulldown Enable Register (PUPD_ENA) Field Descriptions
Bit
Field
Value
Description
31-0
PUPDENA[
n
]
Enables internal pull-up or pull-down functionality for pin group CP[n].
See your device-
specific data manual for pin group information. The internal pull-up or pull-down functionality
selection for bit position
n
in PUPD_ENA is set in the same bit position
n
of the pullup/pulldown
select register (PUPD_SEL).
0
Internal pull-up or pull-down functionality for pin group
n
is disabled.
1
Internal pull-up or pull-down functionality for pin group
n
is enabled.
10.5.23 Pullup/Pulldown Select Register (PUPD_SEL)
The pullup/pulldown select register (PUPD_SEL) selects between the pull-up or pull-down functionality for
the pin group
n
defined in your device-specific data manual. The PUPD_SEL is shown in
and
described in
and
.
NOTE:
The PUPD_SEL settings are not active until the device is out of reset. During reset, all of the
CP[
n
] pins are pulled down. If the application requires a pull-up during reset, an external pull-
up should be used.
Figure 10-50. Pullup/Pulldown Select Register (PUPD_SEL)
31
0
PUPDSEL[
n
]
R/W-C3FF FFFFh
LEGEND: R/W = Read/Write; -
n
= value after reset
Table 10-54. Pullup/Pulldown Select Register (PUPD_SEL) Field Descriptions
Bit
Field
Value
Description
31-0
PUPDSEL[
n
]
Selects between the internal pull-up or pull-down functionality for pin group CP[n].
See your
device-specific data manual for pin group information. The selection for bit position
n
in PUPD_SEL
is only valid when the same bit position
n
is set in the pullup/pulldown enable register
(PUPD_ENA).
0
Internal pull-down functionality for pin group
n
is disabled.
1
Internal pull-up functionality for pin group
n
is enabled.