RTC_SS
20.3.5.17 RTC_COMP_LSB_REG Register (offset = 4Ch) [reset = 0h]
RTC_COMP_LSB_REG is shown in
and described in
The COMP_LSB_REG is used to program the LSB value of the 32 kHz periods to be added to the 32 kHz
counter every hour. This is used to compensate the oscillator drift. The COMP_LSB_REG works together
with the compensation (MSB) register (COMP_MSB_REG). The AUTOCOMP bit in the control register
(CTRL_REG) must be enabled for compensation to take place. This register must be written in two's
complement. That means that to add one 32-kHz oscillator period every hour, the ARM must write FFFFh
into RTC_COMP_MSB_REG and RTC_COMP_LSB_REG. To remove one 32-kHz oscillator period every
hour, the ARM must write 0001h into RTC_COMP_MSB_REG and RTC_COMP_LSB_REG. The 7FFFh
value is forbidden.
Figure 20-77. RTC_COMP_LSB_REG Register
31
30
29
28
27
26
25
24
Reserved
R-0h
23
22
21
20
19
18
17
16
Reserved
R-0h
15
14
13
12
11
10
9
8
Reserved
R-0h
7
6
5
4
3
2
1
0
RTC_COMP_LSB
R/W-0h
LEGEND: R/W = Read/Write; R = Read only; W1toCl = Write 1 to clear bit; -n = value after reset
Table 20-80. RTC_COMP_LSB_REG Register Field Descriptions
Bit
Field
Type
Reset
Description
31-8
Reserved
R
0h
7-0
RTC_COMP_LSB
R/W
0h
Indicates number of
32-kHz periods to be added into the
32-kHz counter every hour
3651
SPRUH73H – October 2011 – Revised April 2013
Timers
Copyright © 2011–2013, Texas Instruments Incorporated