System and Peripheral Control Registers
128
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Architecture
2.5.1.7
SYS Pin Control Register 7 (SYSPC7)
The SYSPC7 register, shown in
and described in
, controls the open drain function
of the ECLK pin.
Figure 2-12. SYS Pin Control Register 7 (SYSPC7) [offset = 18h]
31
16
Reserved
R-0
15
1
0
Reserved
ECPCLKODE
R-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 2-25. SYS Pin Control Register 7 (SYSPC7) Field Descriptions
Bit
Field
Value
Description
31-1
Reserved
0
Reads return 0. Writes have no effect.
0
ECPCLKODE
ECLK open drain enable. This bit is only active when ECLK is configured to be in GIO mode.
0
The ECLK pin is configured in push/pull (normal GIO) mode.
1
The ECLK pin is configured in open drain mode. The ECPCLKDOUT bit in the SYSPC4 register
controls the state of the ECLK output buffer:
ECPCLKDOUT = 0: The ECLK output buffer is driven low.
ECPCLKDOUT = 1: The ECLK output buffer is tristated.
Note: The ECLK pin is placed into GIO mode by setting the ECPCLKFUN bit to 0 in the
SYSPC1 register.
2.5.1.8
SYS Pin Control Register 8 (SYSPC8)
The SYSPC8 register, shown in
and described in
, controls the pull enable function
of the ECLK pin when it is configured as an input in GIO mode.
Figure 2-13. SYS Pin Control Register 8 (SYSPC8) [offset = 1Ch]
31
16
Reserved
R-0
15
1
0
Reserved
ECPCLKPUE
R-0
R/W-D
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset; D = value is device specific
Table 2-26. SYS Pin Control Register 8 (SYSPC8) Field Descriptions
Bit
Field
Value
Description
31-1
Reserved
0
Reads return 0. Writes have no effect.
0
ECPCLKPUE
ECLK pull enable. Writes to this bit will only take effect when the ECLK pin is configured as an
input in GIO mode.
0
ECLK pull enable is active.
1
ECLK pull enable is inactive.
Note: The pull direction (up/down) is selected by the ECPCLKPS bit in the SYSPC9 register.
Note: The ECLK pin is placed into GIO mode by setting the ECPCLKFUN bit to 0 in the
SYSPC1 register. The ECLK pin is placed in input mode by setting the ECPCLKDIR bit to 0 in
the SYSPC2 register.