LM3S1968 Datasheet, PDF (76/525 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 Crystal Frequency (MHz) Not Crystal Frequency (MHz) Using
Using the PLL
the PLL
0x0
1.000
reserved
0x1
1.8432
reserved
0x2
2.000
reserved
0x3
2.4576
reserved
0x4
3.579545 MHz
0x5
3.6864 MHz
0x6
4 MHz
0x7
4.096 MHz
0x8
4.9152 MHz
0x9
5 MHz
0xA
5.12 MHz
0xB
6 MHz (reset value)
0xC
6.144 MHz
0xD
7.3728 MHz
0xE
8 MHz
0xF
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).
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September 02, 2007
Preliminary