LM3S8971 Datasheet, PDF (78/577 Pages) List of Unclassifed Manufacturers – Microcontroller

System Control
Bit/Field
9:6
5:4
3:2
1
0
Name
XTAL
OSCSRC
reserved
IOSCDIS
MOSCDIS
Type
R/W
R/W
RO
R/W
R/W
Reset
0xB
Description
Crystal Value
This field specifies the crystal value attached to the main oscillator. The
encoding for this field is provided below.
Value
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
0x8
0x9
0xA
0xB
0xC
0xD
0xE
0xF
Crystal Frequency (MHz) Crystal Frequency (MHz)
Not Using the PLL
Using the PLL
1.000
reserved
1.8432
reserved
2.000
reserved
2.4576
reserved
3.579545 MHz
3.6864 MHz
4 MHz
4.096 MHz
4.9152 MHz
5 MHz
5.12 MHz
6 MHz (reset value)
6.144 MHz
7.3728 MHz
8 MHz
8.192 MHz
0x1
Oscillator Source
Picks among the four input sources for the OSC. The values are:
Value Input Source
0x0 Main oscillator (default)
0x1 Internal oscillator (default)
0x2 Internal oscillator / 4 (this is necessary if used as input to PLL)
0x3 reserved
0x0
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
0
Internal Oscillator Disable
0: Internal oscillator (IOSC) is enabled.
1: Internal oscillator is disabled.
1
Main Oscillator Disable
0: Main oscillator is enabled.
1: Main oscillator is disabled (default).
78
October 01, 2007
Preliminary