Registers
1342
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Real-Time Clock (RTC)
27.3.20 Scratch Registers (SCRATCH0-SCRATCH2)
NOTE:
Out of reset, the scratch registers (SCRATCH
n
) are write-protected. To disable write
protection, correct keys must be written to the KICK
n
R registers (see
).
The scratch registers (SCRATCH
n
) are 32-bit general-purpose registers that have no effect on RTC
functionality. They can be used by the user arbitrarily. The SCRATCH
n
register is shown in
and described in
Figure 27-23. Scratch Registers (SCRATCHn)
31
0
SCRATCH
n
R/W-0
LEGEND: R/W = Read/Write; -
n
= value after reset
Table 27-22. Scratch Registers (SCRATCHn) Field Descriptions
Bit
Field
Value
Description
31-0
SCRATCH
n
0-FFFF FFFFh
General-purpose 32-bit registers that have no effect on RTC functionality.
27.3.21 Kick Registers (KICK0R, KICK1R)
The kick registers (KICK
n
R) are used to enable and disable write protection on the RTC registers. Out of
reset, the RTC registers are write-protected. To disable write protection, correct keys must be written to
the KICK
n
R registers (see
). The KICK
n
R register is shown in
and described
in
Figure 27-24. Kick Registers (KICKnR)
31
0
KICK
n
R/W-0
LEGEND: R/W = Read/Write; -
n
= value after reset
Table 27-23. Kick Registers (KICKnR) Field Descriptions
Bit
Field
Value
Description
31-0
KICK
n
0-FFFF FFFFh
To disable RTC register write protection, the value of 83E7 0B13h must be written to KICK0R,
followed by the value of 95A4 F1E0h written to KICK1R. RTC register write protection is
enabled when any value is written to KICK0R.