CS Registers
395
SLAU356I – March 2015 – Revised June 2019
Copyright © 2015–2019, Texas Instruments Incorporated
Clock System (CS)
6.3.2 CSCTL0 Register (offset = 04h) [reset = 0001_0000h]
Clock System Control 0 Register
Figure 6-6. CSCTL0 Register
31
30
29
28
27
26
25
24
Reserved
Reserved
r-0
r-0
r-0
r-0
r-0
r-0
r-0
rw-0
23
22
21
20
19
18
17
16
DCOEN
DCORES
Reserved
DCORSEL
rw-0
rw-0
r-0
r-0
r-0
rw-0
rw-0
rw-1
15
14
13
12
11
10
9
8
Reserved
Reserved
DCOTUNE
r-0
r-0
r-0
rw-0
rw-0
rw-0
rw-0
rw-0
7
6
5
4
3
2
1
0
DCOTUNE
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
rw-0
Table 6-4. CSCTL0 Register Description
Bit
Field
Type
Reset
Description
31-25
Reserved
R
0h
Reserved. Always reads as 0.
24
Reserved
RW
0h
Reserved. Must be written as zero.
23
DCOEN
RW
0h
Enables the DCO oscillator regardless if used as a clock resource.
0b = DCO is on if it is used as a source for MCLK, HSMCLK , or SMCLK and
clock is requested , otherwise it is disabled.
1b = DCO is on.
22
DCORES
RW
0h
Enables the DCO external resistor mode.
0b = Internal resistor mode
1b = External resistor mode
21-19
Reserved
R
0h
Reserved. Always reads as 0.
18-16
DCORSEL
RW
1h
DCO frequency range select. Selects frequency range settings for the DCO.
000b = Nominal DCO Frequency (MHz): 1.5; Nominal DCO Frequency Range
(MHz): 1 to 2
001b = Nominal DCO Frequency (MHz): 3; Nominal DCO Frequency Range
(MHz): 2 to 4
010b = Nominal DCO Frequency (MHz): 6; Nominal DCO Frequency Range
(MHz): 4 to 8
011b = Nominal DCO Frequency (MHz): 12; Nominal DCO Frequency Range
(MHz): 8 to 16
100b = Nominal DCO Frequency (MHz): 24; Nominal DCO Frequency Range
(MHz): 16 to 32
101b = Nominal DCO Frequency (MHz): 48; Nominal DCO Frequency Range
(MHz): 32 to 64
110b to 111b = Nominal DCO Frequency (MHz): Reserved--defaults to 1.5 when
selected; Nominal DCO Frequency Range (MHz): Reserved--defaults to 1 to 2
when selected.
15-13
Reserved
R
0h
Reserved. Always reads as 0.
12-10
Reserved
RW
0h
Reserved. Must be written as zero.
9-0
DCOTUNE
RW
0h
DCO frequency tuning select. 2s complement representation. Value represents
an offset from the calibrated center frequency for the range selected by the
DCORSEL bits.